They should just offer a search api and and adwords api together. The publisher can get a cut of the adwords revenue, and there should be some sort of checking that search is being served with adwords - just by looking at comparative bandwith from the one ip.

If Google don't have social in their dna (http://www.youtube.com/watch?v=GyOqNE7H9Ng/), then they should work with those that do.