Interesting thread, I'll kick mine in (June 2002 stats for approx 85k unique visits):
Windows 98 - 42.03%
Windows XP - 18.96%
Windows ME - 18.40%
Windows 2K - 8.11%
Windows 95 - 6.18%
Macintosh PPC - 2.96%
Windows NT - 2.82%
Linux - 0.25%
Windows 3.1x - 0.22%
Sun OS - 0.03%
Which I guess means, MS OS's = 96.72%
Windows 98 - 42.03%
Windows XP - 18.96%
Windows ME - 18.40%
Windows 2K - 8.11%
Windows 95 - 6.18%
Macintosh PPC - 2.96%
Windows NT - 2.82%
Linux - 0.25%
Windows 3.1x - 0.22%
Sun OS - 0.03%
Which I guess means, MS OS's = 96.72%