1. JIT Compiler
2. Exchange-friendly. Tons of new APIs for enterprise users.
3. Application Data Backup. Now, when moving to new phone, information previously stored in an application will come too. In other words, when you re-install the apps you had on your old phone, the new phone will already have all the same settings and information that was stored in that application before.
4. Send to phone API. Example: When reading an article on a PC, you can single-button press and it will launch the browser and open the article directly on your phone.
5. WiFi Tethering