Blender 2.61 is the new release, which notably introduces the Cycles render engine, a camera tracker, an ocean simulation texture, and dynamic paint support.
The Cycles engine is available as an alternative next to Blender Internal. Cycles uses ray-tracing and provides a new shading node system, a new texture workflow, and supports GPU acceleration.
Also sounding quite interesting is their motion tracking support. "Motion tracking support has been added, to reconstruct camera animation from real footage, and composite 3d rendered object into movie clips. A new Movie Clip editor for loading clips, tracking points and reconstructing motion was added."
There are also more than 180 bug-fixes in this release.
To find out more about Blender 2.61 or to download this open-source 3D modelling software, visit this Blender.org page. Blender 2.62 is expected for release in February of 2012.