What is the largest Windows Partition I can make for Windows 7 and still have it formatted FAT for max compatibility with Apple files?

What is the largest Windows Partition I can make for Windows 7 and still have it formatted FAT for max compatibility with Apple files? When loading Windows XP it says to stay at 32GB or less; does this same limit hold true for Windows 7 (is it an Apple-imposed limit) or can a Windows 7 partition formatted FAT be larger than 32GB?