Believe it or not, Apple currently has better and longer operating system support for Windows than it does for Mac OS X.
While Apple's current software will only work on its operating systems from the last four years, MobileMe and iTunes still work on Windows XP from the previous decade.
Of course, that's probably all because Windows XP is still the most popular operating system in the world. TUAW has spotted clear evidence that Apple is drawing a line with its upcoming iCloud service.
In Apple's press materials for iCloud, it states: "Using iCloud with a PC requires Windows Vista or Windows 7; Outlook 2010 or 2007 is recommended for accessing contacts and calendars."
Apple did not specify what, if any, technical reasons prevent iCloud from working with Windows XP. It could all be down to Apple not wanting to devote additional software engineering resources to the older operating system, but it is strange that Apple would risk alienating a large portion of its iPhone and iPad customers.