I see the same thing too.
With my GTX 480:
OpenCL test via Luxmark runs, but gives very low score.
OpenGL Extensions tests yield very low results (around 1500fps).
With my GTX 580:
OpenCL test via Luxmark, gives error that no OpenCL device has been detected.
OpenGL Extensions tests yield the same low results that the GTX 480 got.
Interestingly enough, CInebench yields better scores with both of the cards -- around 40-43 fps, but these are still lower than I got in Lion.