Main updates:

Blender now supports a fully integrated Multi-View and Stereo 3D pipeline

Cycles has much awaited initial support for AMD GPUs, and a new Light Portals feature.

UI now allows font previews in the file browser.

High quality options for viewport depth of field were added

Modeling has a new Corrective Smooth modifier.

The Decimate modifier was improved significantly.

3D viewport painting now supports symmetry and the distribution of Dynamic Topology was improved

Video Sequence Editor: Placeholders can now replace missing frames of image sequences

Game Engine now allows smoother LOD transitions, and supports mist attributes animation

And: 100s of bug fixes and smaller feature improvements.

A lot of people have been calling for better AMD support for a long time. I have an nvidia card so haven't looked at it much, but from reading others complaints it seems that for AMD cards to work at all took a fair bit of messing around. So that's good. Anything to boost competition in this area is always music to my ears.