Here's the cool stuff (the links in the original article were broken, so I've fixed the links here):
- USB 3 support
- CUSE (character devices in userspace) and OSS Proxy
- Improve desktop interactivity under memory pressure
- ATI Radeon Kernel Mode Setting support
- Performance Counters
- IEEE 802.15.4 Low-Rate Wireless Personal Area Networks support
- Gcov support
- Preliminary NFS 4.1 client support
- Context Readahead algorithm and mmap readhead improvements
For me the performance counters will be the most useful thing. Also being able to use and write user space character devices is cool(especially for audio). USB3 support is awesome, but not useful right now... since there isn't even much hardware out yet!
More info on what that low power wireless support is, can be found on the wikipedia: IEEE_802.15.4-2006.