NVIDIA unveiled at its Editor's Day that it has shipped more than 70 million CUDA-enabled graphics chips (beginning with the GeForce 8-series):
According to David Kirk, Nvidia sees 350.000 CUDA-enabled driver downloads every week, while more than 60.000 CUDA SDK downloads were reported.
Nvidia plans to double these numbers once the next generation of GeForce cards is released.
Also interesting to note was a statement from an unnamed Oil & Gas company, which claims that a their current prototype 128 node GPU cluster is expected to outperform their current 4000-CPU cluster system. We somewhat suspect that the quoted company was either Chevron, British Petrol (BP) or Royal Dutch Shell, since these three came have reported the most progress with GPU-accelerated simulation software.