Two related changes from the Recent In-Game Fixes of 04/16:

Double tracking has been a bug for a long time. You would "get" it when you did a server transfer with mining/herb and on the new server you would appear with both enabled. It went away if you did Arenas or manually selected a tracking type iirc. I imagine this is just an extension on that bug.

Just a quick note, Northrend Alchemy Research generates mixtures instead of flasks. Not certain if this is intended or not.

The alchemist caches drop mixtures too.

What is in a cache? I'm guessing they are rare drops also on the boss loot table?

From what people have posted:
~6-10 of most of the different Flasks
~5-10 of various useful Elixirs
1-10 of most of the different potions one would use for raiding (Runic Health/Mana, Speed, Wild Magic)
and raw materials (lotuses, herbs, vials)

It's definitely a decent amount of consumables for an alchemist to pick up.

I think they're looking for a different way to alleviate the consumable requirements other than using Marks of the Illidari. To me, this seems like a better solution than dropping marks that they have to bandaid to work for every new raid instance they will release in wotlk.

They drop "Mixtures", so that's twice as many flasks as listed. I got total 2 x (5+4) flasks from single cache.

This certainly adds a different dimension to the "profession perks" mechanic for alchemists, in that if you don't have an alchemist in the raid, you don't get this benefit. Correct me if I'm wrong, but new enchant formulas drop regardless of whether or not an enchanter is in the raid, right?

Bottom line is that this definitely enforces that a guild should diversify their professions in order to maximize their loot from boss drops -- though I wonder what happened to Alchemist Caches showing up from other bosses than just Freya...

Flame Leviathan and XT-002 can both be "skinned" with engineering. I got 16 saronite bars, some engineering parts, and a few eternal earth and shadow from XT. So there's a small benefit to having an engineer in the raid also.

Edit: got a titansteel bar off XT this week.

Odd unannounced change - the minimum level for the Dalaran cooking quests has been bumped up to 77, from the old requirement of 65. I really don't understand why the levels changed; are there new high level aggro mobs by the carrot spawns? Sewer Stew is the only quest that requires items outside of Dalaran to get, which makes it the most likely reason the dailies got a level increase.

Jewelcrafting daily can certainly be done at 70, I think even at 68. My 72 priest does it nearly every day, and much of the XP she used to get from 70 to 72 is due to this.

Jewelcrafting daily was bugged with 3.1 to stop working below some upper 70s level (maybe 77). They hotfixed it. Then they launched 3.11 and it was bugged again to not be available in the low 70s. They hotfixed it again. Further proof of shaky version control. But, yes, my 72 paladin is back in business, having lost the one day.

I can confirm it being fixed as well - I just did the Cheese for Glowergold version on a 74 character.

WoWHead lists level 65 as the required level for all the jewelcrafting dailys, and this corresponds nicely with my experience - my jewelcrafter started doing them at level 66 (at which point some of them are actually marginally challenging ,-P)

EDIT II: Hmm... being at 68 when 3.1 hit, I know I did it multiple times between last Wednesday (patch 3.1 EU release) and Sunday, and have done it this morning (patch 3.11 hit EU on the night to yesterday)... On the other hand, I didn't do it yesterday having forgotten to hand it in on Tuesday (bleh), and I believe I wasn't able to accept it on Monday for what I now, in retrospect, assume is the bug described here.
So yeah, I guess my contribution here isn't as useful as I initially thought. Sorry and feel free to delete .-P

From the recent ingame fixes post:

So depending on relam and RNG lcuk you never got a wrong quest on your realm, and always had the ones still available at level 65.
Anyway, it's fixed now.

I think "a bit" is an understatement, but I can see where they are coming from. Essentially, JCs could ignore most socket restrictions by sticking Dragon's Eyes in the not-so-favorable-colored sockets, and still got the socket bonus, while ignoring meta gem requirements entierly. This will bring Jewelcrafting's stat bonus much more in line with the other professions.

Still leaves Jewelcrafting better than the rest for most classes for now, due to the more flexible choice of stats.

I can see where this is coming from, no doubt. I'm curious though what they're going to do once "normal" epic gems hit.

As a tank all I'm interested in (mostly) is stamina. Assuming they leave it as it is now, JC will be worth 3x11 stamina over the normal 30 stamina gems. No more additional stamina (or other socket boni) for ignoring socket colour. Mining will still be worth 50 stamina, BS 60. LW 50, as well, Enchanting 48. Are they going to intruduce, uh, legendary JC-only gems, at around 46 stamina each, for a 3x16=48 bonus over epic gems?

We'll see...

This is probably the way the change needed to be done so that the benefit was more even across the board instead of dependent on the seemingly random socket bonuses your current gear has or what metagem is optimal for your class/spec. Plus, adding another tier of dragon's eye cuts (or whatever) is an easy solution and very controllable as far as the increased benefit over epic gems.

A lot of people seem to think Tailoring is next on the chopping block but I'm not so sure. Blizzard seems to put a large handicap on random proc-based things. Just look at the Greatness cards or the badge trinkets.

Yeah, the more I'm thinking about it, the clearer it becomes what they're going to have to do. They can either not introduce epic gems at all, leaving all (well, most) professions just about equal, or they can introduce them, but they'll have to buff all stat-related perks to an equal 60 stamina (or the equivalent for the other stats).

If and when there are epic gems, there will be a new tier of JC gems. Blizzard aren't stupid. If anything, this change is long overdue. JC will remain one of the strongest professions due to the flexability provided by having bonuses in stats other than AP/SP/stam.