Users of NVIDIA's Quadro 4000 workstation graphics card may have a problem with 3D acceleration when updating to OS X 10.6.7.



From TUAW:

Apparently NVIDIA's display driver was incompatible with OS X 10.6.7 and during the installation process the updater simply removes it. Without having the right driver the system can't take advantage of all the Quadro's features, and you may end up wondering why some things aren't working.

  OS X 10.6.7 update causing problems with 3D acceleration for Quadro 4000 users