I'm pretty sure the answer is no. Video out will be out only. I don't believe the OMAP SOC which the Pandora is using has video-in functionality as an option, but check the WIKI links to be sure.
Yea. My Digibox HD recorder is getting pretty full and the DVD recorder that was previously use for backups has been repossessed so it would be awesome if I could back up the videos to Pandora using a little usb-composite adapter.
There must be plenty of these around with linux drivers, anyway, right?