Menagerie: not yet released
Toxin: not yet released
They will focus on different types of damage. They will have some affiliation and multiplicative power with the three primary talent choices: Survival, Beast Mastery, and Marksmanship. One of them will likely have PvP applicability.
We know this from looking at the other pure DPS class level 75 talents.
WarlockWe also have a strong belief that Menagerie is the "call all your stabled pets out for a massive attack fest". This would seem to benefit all types of hunters, but BM would likely get the most bang for the buck.
http://mop.wowhead.com/spell=108499
http://mop.wowhead.com/spell=108501
http://mop.wowhead.com/spell=108503
Mage
http://mop.wowhead.com/spell=114923
http://mop.wowhead.com/spell=44457
http://mop.wowhead.com/spell=112948
Rogue
http://mop.wowhead.com/spell=51626
http://mop.wowhead.com/spell=108215
http://mop.wowhead.com/spell=108216
Toxin sounds to me like a DPS boost via a DoT. They had all sorts of different ammo types in earlier drafts of MoP so I would guess that this makes all your shots poisoned either for a while after activation or indefinitely.
There is a Warrior minor glyph, "Murder of Crows" which has body text of "Your Execute critical strikes summon a flock of carrion birds." It sounds pretty cool and hunters do have the almost equivalent, Kill Shot, so it might be an elevated talent instead of a minor glyph. Or it may completely go away. Or it may adjust how Aspect of the Hawk works.
EDITED TO ADD: Bah!!! Everything is different now. Different talent names even.