One way of looking at it: What are Flickr! users using?
“Over a year ago I proposed collecting EXIF data (the data on the type of camera, settings, etc, generated by digital cameras for each photo taken) from Flickr, the online image sharing service, as a means of better understanding which devices correlated with which kinds of images, times of day taken, locations taken etc. Bighugelabs.com has now gone out and collected this data to see which camera types are most popular.”
They still need to aggregate camera names that differ on international versions, but this is interesting data.