Additionally, Premiere Pro now supports the new GT 650M graphics card that is found in the new Macbook Pro models. Premiere Pro can use either OpenCL or CUDA for GPU processing on the GT 650M.
Premiere Pro CS6 also received Windows 8 certification with this update.
You can download the update from within Premiere Pro CS6 by choosing Help > Updates, or via the Adobe Application Manager.
[via Adobe Blogs]