Just my two cents about the "underexposure problem" that pops up on threads. I have not seen it at all on my D100. Maybe there is some difference not found in Nikon's quality control.
One thing I don't get about it. If it is underexposing, why not simply give more exposure, just like film? You can look at the LCD to tell. Maybe I am missing something. I wish there were more owners of S2s and D100s to compare the two in a more statistically correct manner.