Infiniminer, and Notch has been very up front about drawing inspiration from it. I haven't played it myself but several people on the Escapist forums have said the gameplay between the two is very different even if the aesthetics is similar. I haven't seen anyone counter that so I don't see any reason not to believe it.
I enjoy Mojang and I very happily voted for them in the first three rounds. Then again the last Nintendo system I owned was the NES, I've never done much with Namco Bandai, and the last time I played an Epic game much was the original Unreal Tournament demo. A developer I like versus developers I don't care about? Hardly a contest there.
I voted for Obsidian in round four but I may go back to Mojang for the semi-finals. I really like Valve and I can't wait to play Portal 2 but their release schedule leaves a lot to be desired and the Half Life games are painfully linear. I understand that a strong story requires a certain degree of linearity but the gameplay in between story points doesn't have to be so firmly on the rails, loosen up Valve!
I'll be voting for Bioware over Blizzard, no question there. When the Star Craft II's single player campaign in fully released I'll pick it up and may change my mind about them but here again is a developer I just haven't had much recent contact with.