I'm kinda going with what the artical says. It is basicaly FUD genereated by Microsoft. For as far as SCO claims go M$ will spin anything to make it worse and the I.T world knows it. It also knows that M$ has lied on many occasions.
its obvious.
So the majority, if you could call it that, would be windows2000 customers switching to win2003 because windows 2000 just plainly sux! and even then most of those customers have or will switch to linux due to the cost of upgrading to 2003 and the EULA just isn't worth it.
I can see a similar thing happen to the home user.
If the home user isn't happy with his/her 9x machine then they would probably switch to Linux or stay where they are or even down grade (i've done that with win95). There realy isn't a market for things like longhorn or win2003 just because the old stuff works and the alternative is better!
and upgrading! costs way too much however way you put it!