seven skies online
its an open registration beta right now, since they need more testers, but its ROSE with a lot of new customized things like skills and whole new 3rd jobs (eventually).
The Darkspore beta is pretty good, but man I can't see myself justifying shelling out $50 for it when Torchlight II is gonna be $20. It's definitely the best thing to come out of Spore though.
world of tanks, which isnt going to be beta much longer. Black prophecy, which I deleted because tbh its not good at all (lol), and Battlefield play4free