I just got my Tribes: Vengeance Beta working today, and I tell you, I love this game!
You guys should really try it out! It has GREATLY improved over its predeccesor, Tribes 2. It incredibly fun, although it has some bugs here and there, but you can't blame it, it clearly says it's a Beta, besides most of them usually don't interfere with having a great time.
Go here now, and sign up today!