An Update Focused around Mobs?

Tweaking, Adding mobs and Mob Variants should be a focused update for minecraft. Rather then getting one or two mobs from a update it would be lovely if we got an updated on mobs for all the biomes (think aquatic update but all about mobs instead of the ocean!).

I've seen loads from the community about adding different mobs to various biomes and it is one of the highest with request besides Blocks, Tools, and Items. Not to mention the more there is to see in a biome the more people will want to try and find some of them (especially the more rare ones).

Biomes really need to feel like there is life too them and not with people but animals, real or fantasy ones!

And with this update it would be great if Mob Eggs had their own tab to look though instead of being part of another tab!

Now before you ask, does the ocean really need more? Yes. Mainly Jellyfish. Give me these Jellyfish.