You are assuming that most people will abandon XP when it is officially abandoned, I'm not sure that lack of official support will convince users to embark on a disruptive upgrade to Windows 8.

There are signs that the rate of decline is slowing: http://gs.statcounter.com/#os-ww-quarterly-200803-201303 I think our best bet is that residual users switch to a better browser on XP.

XP is currently on 20%, but IE8 is at 8.5%: http://gs.statcounter.com/#browser_version_partially_combine...