Linux 3.3 has been released Officially with Android support
Linus Torvalds has released Linux 3.3 on 18 Mar 2012.This release is important as it also features the merging of kernel code from Android project. It also includes support for a new architecture (TI C6X) and much improved balancing and the ability to restripe between different RAID profiles in Btrfs, and several network improvements.
There are also many small features and new drivers and fixes are also available. There are a lot of other changes in Driver and Architecture, virtualization,core kernel, file system management, networking, security,memory management etc.It also has new EFI (Extensible Firmware Interface) boot stub which will allow x86 bzImage to be loaded and executed directly by EFI firmware.
It also includes a project which name is "Open vSwitch". Open vSwitch is a software implementation of a multilayer network switch. This project has existed for years and it's now being merged in the main tree. Linux already has a virtual switch (the Linux bridge), but Open vSwitch is designed for more complex scenarios, and specially to be used as a vswitch in virtualized server environments.
The full changes in features of Linux kernel can be found here.