How to back up Windows 7 on Boot Camp to a Mac-formatted external drive?
Using Snow Leopard Disk Utility, I made three partitions on an external hard drive:


HFS+  for Time Machine
MSDOS, subsequently converted to NTFS, for Windows 7 backup
EXFAT for shared media e.g. iTunes Library


I have not yet made a final decision about what backup package to use for Windows 7.  At the moment, I'm using Microsoft's Windows 7 backup solution, with manual image files, and trying to keep any data files in the Cloud.

I do not yet have even 10 days experience with this setup.