Thanks again!

It looks like I'm on the original firmware. I just took a look at the wiki, and it seems that upgrading the firmware will wipe out all the data on my device. I'd really rather not do that, since I just spent 4 tedius hours customizing it and transcribing information onto it. Is there an easy way to backup and restore user data prior to a firmware upgrade, or will I need to do it all again?

I know that Nokia and the n900 have a good reputation, but I also know that occasionally other companies have shipped software or firmware updates that come with DRM malware that can turn an open device into a closed device. Before I flash or upgrade anything, I'd feel safer knowing that I can always go back. If something doesn't work out with the upgrade and want to go back, where would I obtain the original firmware?