While Nvidia has certainly made great strides in improving their Vista drivers since launch, apparently they were still late enough to be causing major problems to its customers. Looking at some internal documents that have come out to light as part of the "Vista Capable" lawsuit, it seems that nearly a third of the reported 480,000 crashes during an unspecified period in 2007 came from Nvidia drivers. By comparison, ATI weighed in at under 10%.
Better sales aside, Nvidia was fingered as the #1 cause of crashes as compared to all other sources. What will Nvidia's response to this be? Considering that Forceware drivers were harshly criticized over many iterations following Vista's release, perhaps there is a more serious problem here than simple "growing pains". There are other factors that didn't make it into the figures such as how many people were using outdated drivers, or how many of the crash reports came before newer drivers were available. Still, it is a very interesting statistic.