So, I'm FINALLY on Jellybean (4.1.2) a YEAR after it got released.
DoCoMo pushed the update in August or September, and because my phone is rooted, I had to eventually kill the updater app so it would stop prompting me to upgrade every three hours.
Last time I had to reflash my phone, my backup failed and it took me days to get my phone back in working order. This time it only took about five hours total for the whole process-- a vast improvement. Here's the final process (I made one and a half unsuccessful passes) (this is for future reference to me):
0. Ran a Titanium Backup and then Menu->Special features->Create Update.zip (makes a flashable zip file with the Pro version of TiB)
1. Fired up ODIN 3 v. 3.04. Yes, newer versions are out, but this is the version to use due to a brick bug with the Note and some other phones.
2. Rebooted into Odin download mode (vol down + home). Flashed the update (found on xda forums) under PDA, and allowed the auto reboot to happen.
3. After reboot, powered down and back into download mode.
4. Flashed clockworkmod recovery V126.96.36.199_r12 and allowed auto reboot
5. Held down BOTH volume buttons to boot into Clockworkmod Recovery as the device was coming back up.
6. Wiped the device.
7. Flashed SUper User .zip
8. Flashed the TiB .zip file
9. Rebooted; opened TiB, and restored all missing apps and data.
10. Futzed for a bit with apps that weren't 100% restoreable, widgets, and with system settings that needed to be adjusted to my preferences.
Luckily, I use Nova Launcher as my home screen, so restoring that restored all my icons and their positions. I only had to reset my background.
Bummers remaining: too risky to restore Wifi access points, so need to put them all in manually again as I encounter them. Boo. Also, BTsync seems to be ignoring new photo files. Will have to investigate that today.