Dota 2 release date is now sometime this summer. I don't think much will change in terms of gameplay. The game feels really polished and finished now, though they do major balancing patches every month or so. It seems like most games release then patch, dota2 has been faithfully sticking to beta status while they tailor it for competitive play. I think they really want it to thrive as an e-sport. It's supposed to keep the free-to-play model so should be able to play for no cost. Right now only additional aesthetics cost anything like hud themes and different outfits for heroes.