I especially liked the 1.5 java extension they are going to support.
I know it has been a big fight to get the generics in Aurora so I am not really pushing hard but damn jsr-201 looks really sweet. No more ugly loop syntax. Ruby to the rescue ;)
Here is an extract from the above link
generic types (jsr-014)
enhanced for loops (jsr-201)
static imports (jsr-201)
metadata facility (jsr-175)
compiler APIs (jsr-199)