Well, I may have messed up my NC in record time.
I got the NC today. I fully charged it, and ran through the initial setup. It was running 1.1.0 right out of the box. I changed the desktop wallpaper, looked at the quickstart guide, and played with the browser for a few minutes.
I took a look at this thread, and decided to try out the "8 interrupted boots" thing, just to see what would happen. (I was curious if the software version would drop back to 1.0.0, or if it would just stick at 1.1.0) After the 8 boots, it did the software install, right on schedule. Then things started getting weird....
After the NC booted back up, the main home page wallpaper kept flashing on and off, and an error box with a message that began "Initial loading from the Media Provider failed" kept flashing up. I was able to navigate to Settings, and the software version is now "Unavailable". At this point the "Home" page would only display for about 1 second, before switching back to the last thing I was viewing. (Settings, the browser, etc.)
I decided to press on with the OP instructions, in hopes that the NC would feel better after installing the 1.0.1 Sideload_update.zip. I copied it over, but so far, the NC shows no interest in starting the update process when I put it to sleep.
Any ideas? Should I do the 8 boot thing again for luck? Should I install that Adobe thing in hopes that will make the update install?
[EDIT] I tried the Adobe Digital Editions thing. It had no effect that I can detect. (ie. its not updating itself) I'm going to try replacing the 1.0.1 Sideload_update.zip file with the 1.1.0 version.
[EDIT 2] Nope, that didn't work either. I also tried the "Erase and Deregister Device" option in Settings. It's been sitting on the "Deregistering device..." page for several minutes, so I kinda suspect
that isn't going to work, either.
[EDIT 3] My suspicions were correct.

I tried another 8-unsuccessful-boot sequence, this time with the 1.1.0 sideload file copied to the NC. I thought maybe it'd grab that file and get me back to where I started. Nope.
I suspect I'm screwed, at least until my SDHC cards arrive. It would be nice to get some advice, however.
[EDIT 4] Fixed! Thanks for all the help. I'm running 1.0.0 now.