Sorry for the late response -- I rarely check those messages on Macrumors. Using one disk for backing up both Windows and OS X will be a problem, because the only shared file system that both can actually write to is FAT32, and that has several restrictions. However, you could install the shareware MacDrive in your Windows installation, that will allow Windows to also write on OS X partitions/file systems. For me personally, this whole OS X and Windows 7 thing has reached a point where I am seriously thinking about dumping OS X altogether. I make my living in a Windows and Linux environment, and based upon my experience, OS X is by no means a better platform than either Windows or Linux. It just costs more, and I am no longer willing to pay the Apple premium. I still like their hardware a lot - Macs are great Linux and Windows machines.