A lot of the threads at guru3d are reporting glitches with the new drivers.
I doubt there was any conspiracy by Nvidia, the drivers increase the efficiency of the Vertex and Pixel Shaders, hence anything that used them will increase in performance. This means that certain tests on 3d Mark (Nature etc.) will get big hikes and as these tests are weighted higher it naturally increases the overall score dramatically.
This also means that games, which support Vertex/Pixel shading will benefit, seen as a lot don't you are not going to notice a huge amount of difference.
Personally I haven't looked at the drivers yet, I will tonight when I get home. I do use 3dMark, but usually only to test for stability as the scores can be easily rigged and I only benchmark for my own benefit.
Interestingly, there were some reports of improved FSAA, so I will be interested if these drivers have removed some bugs as when I enable FSAA on my Ti4400 it causes all sorts of problems with load times on some games.