This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff 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.