Borderlands 2 is shaping up to be an interesting game, capitalizing on the strengths of its predecessor and throwing some interesting new features into the works, including the just detailed new class: The Gunzerker.
According to Borderlands 2's lead writer Anthony Burch, speaking to IGN, "I can combine a shock machine gun and a fire shotgun and charge with my machine gun firing to drop [enemy] shields and then light them on fire with the shotgun at close range and melt their face." Sounds good to me.
If you played Borderlands, you'd be expecting elaborate skill trees to go with the new class, and you won't be disappointed. There are three Gunzerker trees to branch out in, the utility of each depending on your playstyle. Burly fighters will enjoy the "Brawn" tree. Crazy MFers will like the "Rampage" line. Tech heads will put their points into "Gun Lust." All three of the Gunzerkers trees, as well as a character back story, are available at the "Source" link.