IE9 will not work on windows XP as a system requirement declared by microsoft:
http://ie.microsoft.com/testdrive/in...s/Default.html
will you switch your XP and buy Windows 7, or (god forbid) buy Vista just to use IE9 ?
a lot of XP users will stop using their IE7 or IE8 because of security issues that come with an old browser ... and try google chrome or firefox.
as for me: ask me after I switch from XP i'm using now to Windows 7 which will be more than a year from now