Recently I stumbled over a link to this site:
Using Photographs to Enhance Videos of a Static Scene. These guys have developed a very cool technique where they blend high-resolution images into digital video to enhance picture quality.
Check out the demo video of the process, it is very impressive what they have accomplished.
I for one am certainly hoping their tool will be available at some point. It would sure help improve some of my own video captures. Not just by enhancing quality, but also making hand-held clips stable in motion (about 4 minutes into the video).
As they say, there are already tools on the market that help stabilize video, but their technique seems to be the winner.