Blender 2.62: Cycles
Multi GPU Rendering
The GPU devices used for rendering can now be selected in the User Preferences, in the System section. There is a choice between CUDA and OpenCL, and one GPU or all GPU's. Once this is configured, for each scene it's then still possible to select CPU or GPU rendering (usually depending if the scene is expected to fit in GPU memory). - r43238
Render Layers and Passes
Layers can be used to split objects in the scene into multiple layers that can then be individually tweaked and composited together.
Passes can be used to split rendered images into colors, direct and indirect light to edit them individually, and also to extract data such as depth or normals.
Environment Map Sampling
Rendering of more complex environment maps is much less noisy when enabling the new Sample as Lamp option in the World properties. This option will analyze the environment lighting and allocate more samples to directions where more light is expected to come from.
In a preprocessing steps, the environment lighting is 'baked' into an importance map, and the resolution of this map can be configured. A higher resolution will better detect small features in the map and give more accurate sampling, but conversely also take up more time in preprocessing. - r43567
For renders where only the camera or materials are changing, while meshes stay fixed, it is now possible to skip the sometimes slow BVH step, by enabling BVH Cache in the Performance panel. This will store the BVH on disk for subsequent (animation) renders of the same scene. Note that if the scene does change in the animation, enabling this option will make rendering somewhat slower. - r43422
For a render, it will save bvh files to the cache user directory, and remove all cache files from other renders. The files are named using a MD5 hash based on the mesh, to verify if the meshes are still the same.
A Checker texture nodes can be used to easily generate checkerboards. - r43223