Thanks! I followed all that, and it all seemed to work out. The RUU went without a hitch, I flashed TWRP 1.1.1, and then flashed the May 28 MeanROM 1.7 ICS. My phone now boots through the load screen and shows the wallpaper briefly, but then resets itself. I should have the right firmware now, but it still isn't quite there. It's close, but not there.
I'd be willing to try another ROM, too, if you've any suggestions. I really don't have my heart set on any in particular, just one with some good features and perhaps a working camera.