This past week, while researching for another post about IE8 and responsive design I'm thinking about writing, I pulled stats from a large number of Google Analytics profiles on all of the widths of the screens, and created a histogram.
I fully expected something that looked like a bell curve of screen sizes, especially in the desktop range where people can resize their browser windows at will. But instead, even at those desktop sizes, there were some screensizes that vastly outpace other screensizes.
The largest spikes were around 1024px (16%), 1280 (27%), and 1366 (15%), and I frankly I have no idea why that would be.