What We Know: The Level 75 MoP Hunter Talents

Murder of Crows: not yet released
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.

Warlock
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

We 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.

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.