There's an interesting discussion at TSS about the Servlet 3.0 spec. Two noteworthy things coming from the new spec are continuations, and annotations.
Continuations are great... they're already implemented in Jetty and Tomcat - subjectively, Jetty's approach looks better - and are a brilliant way to break away from thread-per-request processing, allowing better scalability and interesting new ways of doing things.
Annotations... eeeeh, not so much. Annotations are great when used judiciously but they must have turned into one of the most abused features in Java. Sure it might be convenient to specify your paths and mappings in a POJO and start specifying arbitrary methods as GET and POST handlers, but by the time you do that, you no longer have a POJO... you just have lots of hard-coded configuration in the guts of your code. Thumbs down from me.