The SuperGa
I haven't tried it out, but the gameplay video of it that I saw left me a bit wanting. It looked like it had a lot of potential but made me glad that the video said the game was still in beta. I don't know if it's out of beta by now or not.
I don't believe it ever went into an official beta. They released it to the public directly from Alpha, and will continue adding content and fixing bugs, performing tweaks as times goes on, similar to what Notch does with Minecraft.
Gameplay video can be mixed. It depends on who you are watching play. My best advise would probably be to find a good Let's Player like Northlion, that is fresh to the game, so you are experiencing the game as they are to get a true feel for the game.
I wouldn't have been very interested if I first saw it in a video of people running around with high tier gear tearing through the game. It's all about progression.