Very soon, computers running Microsoft Windows XP without Service Pack 2 installed will not be able to block the upgrade. Yes, its time to get SP2 pushed onto you. The magic date is Tuesday, April 12th.
"Because of these significant improvements, Microsoft views Windows XP SP2 as an essential security update and is therefore distributing it as a "critical update" via Windows Update (WU) and the Automatic Updates (AU) delivery mechanism in Windows. Microsoft strongly urges customers with Windows XP and Windows XP Service Pack 1-based systems to update to Windows XP SP2 as soon as possible."
The April 12th date is also the same day that Microsoft will release a number of security patches as part of its monthly scheduling of security updates.