May be I'm incorrect but I think that the new Lifeblood that provides 240 haste for 20 seconds every 2 minutes could be a little good. Isn't it?

Resistance is Futile:
Ok, maybe here I got a little confused.
a.) After proccing it gives you a buff, which gives you back the KC focus cost, OR
b.) You cast a KC, and IF it procced, you get back your focus cost?
If b.) then nevermind, it just junk.

MfD is our best options to reach Chimera Shot.
We got the other following choices:
- Rapid Killing: Minimal DPS, when you can KILL an adds.
- Silencing Shot: Melee interrupts are far more effective, than this, and in a 25-raid there is almost always a melee who can interrupt much faster than we. (Of course, for 10-man raiding it is good for one point.)
- Concussive Barrage: Do not work on bosses.
- RiF: stated as above.

From theese choices MfD is our best talent, it mean 1 free GCD every time when you switch target. (In single target fight it means nothing, except it is longer than 5 minutes, and there is no time to refresh HM.)

Corrected: Pet number, hitcap, Herbalism.

I would wonder where is the best place for our remaining 5 points.
Our choices: (No, I don't consider HvW, until we hace too, but at the momemt it is not neccessary.)
One With Nature: 162 AP / point
Bestial Discipline: 10% more pet focus / focus
Pathing: 1% haste /point

I don't think that just by looking at them you could decide what is the best place for 5 point.

All-in-all a good compliation of information. I have several comments on the OP though:

1) I am a little surprised by your suggested spec. The concerns I have are:

a) You have 2/2 CA, which may or may not be okay now (although it will definitely be needed when get to 85). If you have greater than 40% crit rate (which all MMs should in Wrath), then much of that second point is wasted. I anticipate having about 60-65% crit raid buffed after the 4.0 conversion of ArP on gear to haste/crit and then regemming. Unless I reforge some of the crit to mastery, which I do not plan on doing until I understand the trade-off better, the second point in CA may not be too useful. However, if your crit rate is enough lower than 70%, it is still probably better than other options.

b) You have 2/2 Sic'Em. Although I believe that this will be a must in Cata when we first get 85 and to also help with Wild Hunt, I do not think that 2/2 will be that beneficial now with how high our crit rates are. It may be better now to mave that point into Rapid Killing for the extra focus regen and damage after getting a killing blow. I am not certain about this yet since I haven't played around with pet focus with the changes yet, but its something to be aware.

c) You do not have Silencing Shot. I thought about not speccing into it either since it no longer does DPS, but then others persuading me to keep it. It stil does not cost a GCD, so you can still macro it into every shot. When it does happen to silence a caster, it will save the raid from possibly taking additional damage or adverse effects. Furthermore, the Silencing Shot major glyph is one of the few useful ones for MM. Getting back 10 focus from a free shot that also helps the raid, can be a DPS boost.

d) It's preferrential, but I see no reason not to take TSA. That way you have the huge benefit when soloing and are guaranteed to have it when doing dungeons and 10-man raids. Sure other may also provide the buff in dungeons or raids, but what if they die. In my opinion, there really is not anything better to spend the point on to not take it.

e) Termination may not be needed at all depending on your situation. If you have enough haste to get you SS cast time down to 1.5s with Pathing and ISS (which should be easy with the ArP conversion to haste) and have the KS glyph with doing back to back KSs, I show that the extra focus from Termination can be wasted since KS takes no focus. The only times that Termination can be useful is if you decide not to keep up the ISS buff during the last 20% (which hurts you autoshot damage and mastery) or if have dynamic haste effects over that period like Rapid Fire, Blood Lust, or Speed Pot. However, since RF is giving a lot of focus at the moment, especially with RR, Termination is not needed with RF. It can be useful with Bloodlust and Speed Potion though so that extra GCDs can be used on ArS, but it is not required since your SS cast should be around 1s then and can be used to quickly regen focus if needed in one of those two extra GCDs.

f) The Aimed Shot glyph does not seem like a good option. From my analysis, with doing 4 SSs per 10s CS rotation, you should only be getting an MMM proc about every 2 rotations or 20s. Thus, this glyph averages out to about 0.25 fps if you critically hit every Aimed Shot. If you crit every other Aimed Shot, then the regen is halved to 0.125 fps. I would think that the Arcane Shot glyph for 12% additional damage for ArS (this is upped from the 6% you list) would be much better, especially considering that ArS is going to be our second most used shot after SS. When under normal haste affects (raid buff and ISS), I anticipate doing 2-3 ArS per cycle, and even more when under temporary haste effects like RF, Bloodlust, and Speed Potion. Hence, that glyph should be a huge benefit.

g) Although Disengage is a fun talent and is useful situationally, I do not think that the 5s reduced CD will be beneficial on most boss fights. I believe that the Silencing Shot glyph is a must since it is essentially free focus return on fights with caster targets. However, if the fight does not have a caster target and is one with can be Disengage intensive, then I would switch the glyphs for that fight.

2) Concerning the priority, some thoughts:

a) For priority, since you have specced MfD, I would not worry about ever applying HM except for out of combat since MfD will take care of making targets in combat for you. Hence, it can be taken out of the priority.

b) There are debates on this, but personally, I would prioritize doing an SS pair to maintain the ISS buff over using an MMM proc. Since it takes on average 8 SS to proc MMM, wasting one chance to proc a stack if MMM procs on the first of an SS pair probably is not as much of a loss as compared to temporarily losing the ISS buff or having to change your rotation to maintain it. The trade if about 6.25 AiS average damage (50% chance that MMM will occur on the first SS in a pair with it requiring 8 SS casts for MMM) versus 2-3 seconds of ISS downtime and longer SS casts to regain it throwing off your rotation and possibly losing a GCD that cycle. Which wins out is hard to say at the moment.

c) As others have pointed out, you do not have KC in the priority if specced into it. I would put it below the priorities for both a SS pair for ISS and MMM procs.

3) For those questioning RiF, there are indeed still a lot of questions concerning it that have to be answered before we can fully analyze its benefit. However, with the items I listed above concerning some of the talents, I really do not see a better option for those points and plan to spec it to at least test it out, so I can see the following:
- How often it procs under various conditions
- KC to ArS relative damage and focus savings (since it would be replacing an ArS normally in the rotation)
- Even if the damage between KC and ArS ends up being even, KC with this proc costs 22 focus less. With the "optimal" MM rotation (with Pathing, over 15% haste from gear, and ISS) with CS, ArSx3, and SSx4 costing 24 net focus per cycle and requiring a focus correction cycle of CS, ArSx2, SSx5 every 2 of 3 cycles (this cycle regains 10 focus), each KC proc from RiF actually balances out focus on the optimal cycle and saves 2 ArS over 2 SS over the long haul. AiS procs from MMM have similar positive rotation impacts. Hence, although RiF and MMM procs replace ArS shots in the rotation, the focus saving that cycle will actually allow more ArS on future cycles.

4) For those suggesting Concussive Barrage, generally I see little benefit to it in raiding. It has no DPS benefits. In fact in some situations, it can actually be counter productive since it will slow a mob that the tank is trying to move someplace. It is true that CB may have benefits on certain fights where it helps with CC and survival (like with some Faction Champions strategies when it was being learned), but I believe that those will be the exceptions and not the norm.

As for the argument over and of the viability of SilS in raids, it has been discussed deeply on various posts and threads, comparing it with other classes' interrupts. There is however, at least for content that is left in 4.0.1, one benefit for speccing into SilS, that is when someone has not beaten LK in normal mode. Getting pulled into Frostmourne as Survival before outgearing the encounter was not easy. At least for 4.0.1, we have another option of bringing an interrupt pet I suppose, but it's not like we're having much choices in appealing DPs talents when it comes to that single talent point you're going to put into SilS.

As for future raiding application (as in Cata), there may or may not be any boss encounter requiring any individual interrupt like LK. It is intended to be a utility talent after all, something that whether you want to spec into it depends on encounter and raid comps, especially with the possible prevalence of 10m raids as compared to 25m raids in cata.

Here is what I am currently leaning to for level 80: 2/31/3
Note:
- The 2 in OwN could be moved to IKC if RiF procs enough to make it worthwhile. With so many questions with RiF, I prefer the constant AP on essentially all attacks.
- If our crit rate is enough below 70%, then moving a second point into CA would be done. This point would probably come from RiF
- If I see with Wild Hunt that my pet is not maintaining its focus high enough often enough despite the high crit rate with 2/2 GftT and 1/2 Sic'Em, then I would move another point into Sic'Em, probably from RiF.
- Concerning Silencing Shot, I was persuaded to spec it even before the glyph became available just because of the fact that the macroed use of it will silence casters and improve raid survivability and the small situational uses of it as a ranged interrupt. The glyph is just an added bonuses to already having the shot and the fact that there are not really any DPS beneficial major glyphs for MM. Plus, anytime you did get the 10 focus, it would help counteract part of the focus deficit in the "optimal" MM rotation, but it is nothing something I plan to rely on. Note that I had SilS specced in Wrath since it did DPS. Although I never had to use it as an interrupt, I did see plenty of times in logs where it did interrupt the target although I was not even trying to do so.
- I feel very good about the remainder of the points such that they need no explanation.

At 85, I currently plan to spec 5/33/3 if RiF pans out and 7/31/3 if RiF is not beneficial.

Note:
- These specs have 2/2 CA and Sic'Em since they should be needed at level 85 with relatively lower end gear and with crit rate scaling on bosses with tier progression.
- It is possible that if my haste (SS cast time and focus regen) is low enough that I may move a point in the BM tree into Termination.

Have you also mentioned that pets also scale off 100% of their masters' haste and crit? With spider's bite (assuming the use of a ferocity pet) and the base melee critical strike chance, they will always have +15%~ more crit than their master.

I would also add to the consumables list strength scrolls for the pet. Currently pets will benefit from strength scrolls and as they no longer receive buffs there is no stacking conflict.

Also to be clear, pets scale with the melee attack speed bonus that the hunter gets, not directly with haste. This means that ranged attack speed and ranged haste buffs (such as pathing and rapid fire) will not buff pet attack speed.

I've pretty much decided that I will not waste both my specs on the MM tree. I would like to be productive, efficient and versatile. With that being said, in order to make that come fruition I believe this MM-Spec (3-31-2) is best suited for me.

Realy the only difference is I only put 1 point in termination instead of 2/2. I put the extra point in SilS for 10mans/Dungeons/PvP.

Now for the bonus 5 points I opted to go with 3/3 OwN and 2/3 Pathing. The reason for this, being that I'm an engineer, so I got haste buff on gloves, I got haste pots, I got talents to imp. haste overall... It just seems logical to me that 30%ap / 2& haste > 20%ap / 3%haste.

Arafeek, that is 234 ap vs 216 ap or 1% ranged haste. I have a gut feeling that the equivalent of 33 hasterating might be better than 18 ap.

Just cuz I'm still not sure of the exact ap gained from the new AotH at Lvl80, I'll provide an example for the Lvl85 version.

1620 x 20% = 324
1620 x 30% = 486

So at lvl 85, it is a 162ap difference. I find it hard to believe that at lvl 80 it would only be 18ap.