Recently I've been watching It's a cable television network (channel 150 for me on digital cable) but the content is mainly user uploaded videos. The web site community votes on what should air, and it's broadcast on the television channel. It's a mashup of television with something like youtube.

It's interesting stuff. There are some issues (like the fact that appointment television is somewhat difficult given that they don't seem to schedule things regularly and their pieces are 5-7 minutes long). This makes it much more of a browse medium - watch for a few minutes and then switch to something else. But that's really the apex of what the MTV format has been pushing towards for years.

I'm not sure if as it exists now is the ultimate solution to viewer created television, but it's certainly an interesting first foray. Worth checking out.