Particles are the biggest update, it will be exciting to see how much they change, its about time you can change particle states.

Big update is the maya assets, im excited to see how much that builds on the issues with the existing referencing system. Container nodes will be fantastic as well.

Render proxy sounds wicked, cuts out alot of manual work if it just swaps geometry and textures and render time for you.

Yay, much needed stuff, so much more impressive than the 3ds max updates.

Personally tweak mode will be a fantastic tool for those used to modelling in lightwave, mirai/wings 3d.