After playing with TM2 for half an hour or so, I don't think I'll be switching back from Vim. I was hoping for some split-screen action and maybe some advanced autocomplete intergration, but it doesn't seem to have either. It's looking to be a great update and improves on a lot of things in the existing version, but if I were honest, I'd have to say I wouldn't bother upgrading if it wasn't free.
That said, it's obviously an alpha release, so who knows what the future will hold.
I don't have a license so I don't saw the alpha but it's seems frustrating that in 5 years of "development" so little was added. But, OTOH, it's not the final version.
Except that if the guts are there to add features quickly, it could have been time well spent. We just don't know yet, but progress over the next month should be indicative (see progress on ST2 as an example of a seemingly healthy codebase in this regard)
Major changes include the new project drawer (though, I prefer ProjectPlus[1]), and the new bundle/theme updater[2], where you just tick the box and it auto-installs.
That said, it's obviously an alpha release, so who knows what the future will hold.