This week's giveaway is in the EJB and other Java EE Technologies forum. We're giving away four copies of EJB 3 in Action and have Debu Panda, Reza Rahman, Ryan Cuprak, and Michael Remijan on-line! See this thread for details.
The EJB3.1 spec has the complete list of what's new compared to EJB3.0. But here's a quick summary.
As for differences between EJB2.x and EJB3, the changes are huge and EJB3 is a vastly simplified version of EJB2.x. If you search this forum, I'm sure you'll find some previous discussions on this topic.