wrong answer greg
by your own reasoning the answer is "yes and no", not "No."
Yes, the majority of upgrading has been done along the way, but no it hasn't kept pace and there is still some "catch up" to do.
You're kidding yourself if you think we could buy more PCs in 2002 than 1999 but somehow be dramatically behind.
I agree there's a tailwind created by the need for some "catch up", but there isn't going to be some kind of boom proportional to 1999-2000 as we "replace" those machines on a 1:1 basis.