Ads are here to stay and if you have to encounter them, why not let them be ones for things you might actually like? I think the voting thing is pretty ingeneous, though i feel there will be some problems:

People don't like extra effort, they are more likely to ignore an ad they don't like than click or move a slider. On the other side of the same coin, they will be more likely to just click on an ad they do like than muck with some sort of rating system.

People don't always know what they like, just because one day they find something attractive doesn't mean a week later or even hours later they will like the same thing.