800x600, 1024x768, 1280x960 are all the same aspect ratio for wallpapers.
1280x1024 is what I use, but it's a different AR.
For a wallpaper submission, perhaps include the top list of resolutions, 1280x1024 seems to be heavily in use here, but It's not necessary to include that -- at least make sure you include a 1280x960 and a 1600x1200.
According to many online statistics, over 80% of people STILL use 800x600 as desktop sizes -- but it seems to be different here. [maybe they need a poll asking just that? *looks at Jafo*...]
Email me sometime, although I'm certainlly not the best here, I can try to help you wherever I can.
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