If you still want an XP computer from Dell, you better order it soon!!! So far I am not a fan of Vista and I wish they would keep XP around longer.
Per the Microsoft® Windows Life-Cycle policy, Direct OEM and Retail License Availability for Windows XP will End-Of-Life (EOL) on June 30, 2008. To meet Microsoft’s June 30 last-day-to-ship OEM Windows XP deadline, June 18 is the last time to purchase a Dell laptop, desktop, or workstation with an OEM Windows XP license.
After June 18th you have the option to purchase Windows Vista Business or Windows Vista Ultimate with a downgrade service to Windows XP Professional. If you transition to Windows Vista, don’t transition because you have to, transition because you want to!