WotLK is really nice so far though - almost all the professions have both equipment that can be used for a while and then ignored, and something that scales and gives a benefit for the rest of your career. Even the farming professions do this! It's really nice that it's no longer a gimpy thing to pick a profession until you get your Tier X item that replaces it, and then have to move on to something else.
The TLDR version: take leatherworking and a gathering profession. If you truly want to min-max, take leatherworking and enchanting or leatherworking and jewelcrafting, as leatherworking and blacksmithing don't work together.
Here's what the associative benefits are:
A really nice, static benefit. This is the best benefit for a feral tank, but doesn't have much synergy with other professions.
Crit strike benefits both cats and bears, but 25 critical strike rating compared to 500 HP? That's kinda sad - it's less than .6% critical strike at 80.
- - use of fire leaf, which increases AP by 400 at the cost of all armor
- - Lifeblood, an instant, free HoT that heals you for 2k and can be used in forms.
A quick heal isn't bad for tanking, and fire seed is pretty decent for DPS. This is probably the best one for hybrid players.
Alchemy: (ETA - thanks Karthis and Ray)
- All elixirs give a bonus of 25% and last twice as long; all flasks give a bonus of 50% and last twice as long.
- Indestructable Alchemist Stone, a fairly nice tanking trinket
- Mighty Alchemist Stone, an okay DPS trinket
This apparently does stack with enchants on the bracer/gloves, which means this is two free, colorless gem slots. That's a total of 60 stam, 40 strength or 40 dodge as well as a lot of flexibility. However, none of the gear that BS makes is useful for druids, which limits its desirability. For min-maxers this is the second-best profession. Pity it doesn't stack with leatherworking.
This is a total of 48 stam or 64 AP that you would not get otherwise. Enchanting does not have any other direct benefits to a druid though, but this benefit by itself is pretty good.
- - Weakness Spectralizers, which are equivalent to T7.10 content.
- - A rocket launcher that attaches to your gloves
- - An on-use haste boost to gloves
- - A really decent trinket for both tanking and DPS
Engineering has the weakest boosts for overall value, but damn if it's not fun. I haven't been able to test whether you can use the rocket gloves in forms. I desperately hope this is the case; I want to shoot a rocket out of my face. For min-maxing though, Engineering loses out. The goggles aren't even as good as T7-25 content, the trinket is marginal, and the haste glove enchant doesn't win against BS, much less anything else.
- - Master Inscription of the Axe which is better than Greater inscription of the axe by 64 AP
- - Master Inscription of the Pinnacle, which is better than Greater inscription of the Pinnacle by 32 dodge
Inscribers can make a lot of off-hand items (including one with +armor, which is almost intriguing), but none are all that useful for a feral. 64 AP or 32 dodge is almost exactly the itemization benefit that enchanting gets. 32 dodge and 48 stam are worth the same, after all. So it somewhat comes down to whether you'd rather have one or the other and what profession you'd rather do. Not the best option, but those shoulders are expensive and it's nice to not be forced to grind even more rep.
A total of three dragon's eye gems of any type:
- - Solid Dragon's Eye which gives +11 stam over the epic version
- - Bright Dragon's Eye which gives 14 AP over the epic version
- - Thick Dragon's Eye which gives 7 crit rating over the epic
- - Precise Dragon's Eye which gives 7 expertise over the epic
- - Bold Dragon's Eye which gives 7 str over the epic
- - Subtle Dragon's Eye which gives 7 dodge rating over the epic
- - Delicate Dragon's Eye, which gives 7 agi over the epic
- - Emerald Boar, a nice AP trinket
- - Monarch Crab, a nice stam/dodge trinket
Jewelcrafting definitely gives the most variety of bonuses. The trinket is the best in slot other than armor trinkets thanks to the sockets for bears, and may end up being best in slot for a while. The gems are all prismatic, meaning they match any socket and any color. That's very nice for metagem requirements and socket requirements on some of our annoying gear sockets. Still, the overall bonuses aren't as good as other professions since you can only have 3 gems total. Either 33 stamina or 21 strength or 21 dodge. That's not so hot. Despite it being not perfect, I'd rank it about the same value as enchanting or inscription because of the flexibility and the trinkets.
- 114 Attack power to bracers, a 76AP improvement over the enchant
- 90 stamina to bracers a 78 stamina improvement over the enchant
I can't imagine the stamina fur lining will make it to live, but if it does it becomes the best by a longshot. The only drawback is that if you go engineering and blacksmithing you cannot have a socket and fur lining on bracers, nor can you have an enchant and fur lining. I don't know why either since the socket does stack with the enchant, but whatever. 78 stamina is by far the best improvement if you're looking for that. Right now there is no BoP leather gear at all; I expect this to change. Even without that, there should be a new version of drums, and that combined with this stamina boost make leatherworking the best profession in the game for bears. For cats, 40 strength potentially from blacksmithing is better, though 76 AP is nothing to sneer at.
- - An AP proc for cloaks, which assuming it's up for 1 minute will give 75 AP per minute; this would beat out 16 agility or 23 haste rating from a cloak.
Tailoring is an odd choice, but the benefit looks ok - if it procs reasonably often. If it doesn't this is probably poor. For a bear it's of no use at all; you'd take defense or agility or even armor before this.