Sarcastic Gamer at PAX2011: "Starting off, its five years after the events of the first game. You’re playing as a new character, whose class is called Gunzerker. His deal is that you can dual wield anything. With that, they showed what else was added:
vehicles will all have room for 4 players
enemies are far more reactive to incoming fire, so critical hits cause them to stagger, shooting their legs cause them to limp, etc.
new characters and character classes.
new locales such as arctic and forest settings..."