I think this is a fantastic idea for the New page. Give people some incentive to monitor it looking for good content. If something they are the first person to upvote makes it out of there, give them residual karma.

My rate of upvoting things out of there that hit the front page is obscene, at least 50%. Assuming that is typical, that means very few people are monitoring that page. I personally would probably not do more of this for karma but I'd imagine many people would. And it may instantly solve the problem of hitting the frontpage being a lottery or determined by manipulation/voting rings etc.