What follows is not my original post ... but a number of us hunters over at TKA Something forums are "all a titter" about how clever and cool the post by Arcazua has turned out to be...
We've been on about it for a number of weeks now and one of the guys Arcuss has even gone and written a fancy-dancy little addon to go with the theorycraft.
We're all interested in hearing more opinions about the addon and theories and weights before they go on and give the goahead and release the addon to the general population (i say "we" like my input is anywhere near what they've done ... it's not I assure you

)
Anyways - on with the post
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Agility Equivalence Points (AEP) was a concept developed by rogues well over a year ago to give a value to different stats on items by relating their usefulness to agility. Some rogues used it; others used their own versions. I'm just borrowing the name.
But this is in sore need of doing. Between changes to both the hunter class and core mechanics, and itemization being completely screwy, it's almost impossible by old standards to know which items are best.
And my synopsis at the end will not answer everything. (For you TL;DR folks, skip down to the bottom.) But hopefully it will give everyone a starting point.
Be aware: all figures I'm using are tabulated for a level 70 character. If you aren't 70 yet, you will be.
While there are other things that matter, primarily, a hunter in 2.0 is going to care about three things -- attack power, crit rate, and mana regeneration. Different stats affect these differently, and the hardest part is that different specs will value them differently. A survival spec will make greater use of crit chance, and a marks build has increased usefulness out of intellect. This is the primary reason why this will not be a one-size-fits-all answer for everyone. However, I will try to account for that most of the way through and only pick my own assumptions later.
ATTACK POWER
Attack power is fairly straightforward: 14 AP = 1 DPS.
To get attack power, there is actual "attack power" on items, or agility also gives 1 point of AP. As a result, calculating value of different items on attack power alone is simply.
1 AP = 1 AP
1 agi = 1 AP
What is more difficult about attack power is that it also scales special attacks by varying amounts. 14 AP may be 1 DPS, but roughly 6 attack power = 1 damage per Arcane Shot, and 4 attack power = 1 damage on Steady Shot.
In order to compare attack power to crit rate, we need to convert both to DPS. This is going to be highly build- and style-based, but let's pretend that a hunter trying to do maximum reasonable DPS - and by reasonable, I mean not completely mashing buttons to go out of mana in 10 seconds - will fire max rank Arcane Shot when it is up, as well as Multi Shot rank 1 (which is far more mana efficient than the other ranks.)
ASSUMPTION #1: In a 10 second period, let us suppose a hunter fires 1.5 Arcane Shots, 1 Multi Shot, and 2 Steady Shots every 10 seconds, and that the steady shots do not interfere with his autoshooting.
Even if we don't make these sort of assumptions now, we'll need them when we look at mana regeneration rates.
So the contributions of 1 AP to 10 seconds worth of damage is:
.821 (10/14 with 15% haste) damage on autoshot
.225 (.15 * 1.5) damage on Arcane Shot
.200 (2.8/14) damage on Muli Shot
.500 (.25 * 2) damage on Steady Shot
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1.746 damage in 10 seconds per AP, or .175 DPS per AP.
In other words, a bit more than merely the 1/14 (.071) that it does for autoshot. You might very well use another shot pattern -- I am not going to use the word 'cycle' to describe your shooting at all in this article -- but it should hopefully give us a good glance at our damage capabilities even if it isn't completely maxed out.
So 1 AP and 1 agi are worth .175 DPS, not counting the effect from crits. This is applicable to ALL hunters, and makes no talent assumptions.
CRIT RATE
Crit rating doubles the damage on a fixed percentage of shots. If you have a 20% crit rate, after firing 10,000 shots, you should expect to see 2,000 of them inflict double damage, meaning you have effectively fired 12,000 shots in that time. This applies to your overall damage, even if it might not in a short fight, and overall damage is what we care about. The only time this would not hold true is when the crit happens when your target has enough health a non-crit would kill them. We're going to forget about that since it makes things needlessly complicated.
Simply put...an X% crit rate will increase your total damage by X%, or X * 1.3 if you have Mortal Shots, but again, we are going to forget specific talents for now.
Crit rate comes from 2 sources: Crit Rating and Agility. At level 70,
~22 crit rating = 1%
40 agility = 1%
So coarsely speaking, in terms of crit alone, 1 crit rating is worth about 2 agility.
Actually putting this into DPS is difficult though, because it is a percentage of your non-crit damage, which means we need to know what your non-crit damage is.
ASSUMPTION #2: The hunter from assumption #1 will deal 2500 points of autoshot damage, 1200 from Arcane, 600 from Multi, and 1000 points from Steady during those 10 seconds, for 5300 non-crit damage. Because as gear improved, this will no doubt be conservative, we will simply call this 6000 damage, or 600 DPS.
On that assumption, 1% crit adds 6 DPS. Thus, from crit chance...
1 crit rating = .272 DPS
1 agility = .150 DPS
Curiously, this is almost as much as our AP amount for agi, which means, yes, agility is about twice as useful as attack power.
While I am here, though, there is one other stat that I have not mentioned that is very similar to crit rating -- HIT rating. Hit rating works more or less the same as crit up until you reach a point where you are not missing. On the assumption that you do not have enough hit rating already, 15.75 hit adds 1% chance-to-not-miss. So for the first 78 hit rating or so, 1 Hit Rating (HR) adds .381 DPS.
ASSUMPTION #3: We do not have enough hit rating for our chance to hit to be capped.