After today, Windows XP preloads are no longer available from OEM’s on new computers. As for XP downgrades , it appears that Microsoft will make them available through January 15, 2015.
Just as a reminder, if you’re still running Windows XP – Service Pack 2 (SP2) expired on July 13th, 2010 and is no longer supported. You need to install SP3 or look into moving to Windows 7 to be running a supported version of Windows. Support for Windows XP SP3 will continue through April 2014.