Actually, if you take the global statistics of more than 1 million people, it looks like this:
800x600 154460354 (54%)
1024x768 84574806 (30%)
640x480 21340104 (7%)
1280x1024 7957872 (2%)
1152x864 7304411 (2%)
Unknown 4711995 (1%)
1600x1200 1155087 (0%)
