New features include improved content-aware tools - including patching, extending, and more. Also includes new blur tools and filters. Performance has been vastly improved, and the interface has been refreshed to match other Adobe products like Lightroom and After Effects.
More info and the download link here.
When I get home from work I'll install it and post some screenshots - it's pretty big at 1.7GB though, so it might take a bit.
Here's some videos on the major new features: