I've read enough horror stories about upgrading Snow Leopard to Lion causing corruption of the Windows 7 partition, and I didn't want to be yet another casualty. So I took the time to research how best to backup in order to prepare myself in case something went wrong.

I started by cloning the Mac OSX partition to an external USB drive using Carbon Copy Cloner. This was drop dead simple, and worked well. There's a complete writeup of this here.

I couldn't get the Mac Disk Utility to clone the bootcamp partition. It would error out with an "Invalid Argument" message. I found a version of WinClone 2.3.2, but that also gave me errors. I finally got it to work by unchecking all of the options in the Preferences window, thanks to comments in this article. I also made sure the USB partition that I was backing up to was set to Mac OS Extended (Journaled). After that, it was a painless clone process.

The actual Lion upgrade went smooth. I didn't lose anything, and everything just worked. One quick note is that you might want to save a backup of the Lion installer if you have multiple Macs that you'll be upgrading. Details on how to do that can be found here.

Off to install MonoTouch for iOS!!