950-1000px is the future
I bet that within a year we'll see ~1200px wide tours too
think about it, most monitors today are at least 1280px wide - those still on 800x600 are probably using old crt's and those sure don't last forever, so they need to go out and get new ones.. and if those aren't available in less than 1280xY then, well.. you figure that out..
anyway, that scenario means that those you still have visiting your sites on 800x600 resolution probably are from very low-wage areas and that they couldn't afford to join your site anyway
In fact, I've heard from a few paysites owners that they don't even WANT 800x600 surfers....