You obviously don’t have much experience with enterprise desktop deployment if you think this is any sort of an issue for an IT department to deal with. What’s even funnier your supposed solution Linux pretty much requires you upgrade EVERY two years to keep up, while Windows XP will be supported until 2014. Name one Linux product shipping today that guarantees security updates till 2014. You’ve got 300 different versions to choose from, surely there is one is currently promising patches till 2014?
two Problems with That
1) My Ideal Solution on the desktop is Apple not Linux despite your obsessive screaming to the contrary
2) RedHat Linux has a seven year support cycle for RHLE which includes their workstation so if you set up some RHEL5 workstations today you could wait five years until you started to upgrade. (Were you ignorant of this or jut lying?)
Name one Linux product shipping today that guarantees security updates till 2014.
Red Hat Enterprise 5 Will be under Full Support (Bug Fixes, Enhancements, and Security patches) Until March of 2014.
Do remember that's for security updates only (what Microsoft decides is security related -- their decision). Anything else wrong with XP won't be fixed after mid-2009 unless you have a contract with Microsoft for it.