Windows (formerly code-named Whistler) will become Windows XP, and Office (formerly code-named Office 10) will become Office XP. The XP name is short for experience, symbolizing the rich and extended user experiences Windows and Office can offer by embracing Web services that span a broad range of devices.
Microsoft announces Windows XP and Office XP
Microsoft Corp. has revealed product names for the upcoming new Microsoft Windows desktop operating system and Microsoft Office desktop applications suite.