Windows 3.1 = #3
Windows 95 = #4
Windows 98 = #5
Windows 2000 = #6
Windows XP = #7
Windows Vista = #8
Yeah, still doesn't work. Maybe they're not counting 2000 and Vista because those were complete shit. Maybe that's the reason for #7 - so they can pretend those two never existed and maybe someday we'll forget about them.
I love XP and don't see any reason at all to upgrade my OS even though Windows 7 has been getting pretty good reviews so far. If I do upgrade it'll be at least a year after it's released, just to make sure they don't pull another Vista on us. But in all the reviews I've read of 7, I don't really see what it does that XP doesn't do, other than maybe eat up a little more memory.