This is Photoscala which published the sales numbers for digital SLR cameras. The most amazingly interesting is -for me- which major brands progressed (or not) between 2006 and 2008:
SLR market between 2006 and 2008
You cannot miss the obvious progress of Sony who clearly became a major actor of this market, and a significant competitor for Canon and Nikon. Furthermore, as could be expected, the leader Canon is suffering most.
But in the end, in a market terribly difficult for all manufacturers, who will come fourth? I can’t avoid believing that Panasonic is doing it right and applying all the needed efforts to topple Pentax, even if nothing is done yet.