Blizzard announced last night that it has released an MoP talent calculator. The thing that makes Blizzard’s calculator different from, say, Wowhead’s calculator, is that it includes lists of the class and spec abilities gained while leveling (credit to Frostheim for noticing that). Importantly, the ability lists affirm just how compartmentalized the spec abilities will be. MM PVPers won’t be able to snag Entrapment anymore. BM and SV will not be able to take Careful Aim for raiding. Commonalities will come instead from the baseline abilities that all hunter specs share and the new talent system.
In general, keep in mind that this is Blizzard’s rough draft of the new system and that more changes are sure to come between now and the next expansion. You can find Bashiok’s comments on the very rough state of the talent calculator here.