Bill Slawski - SEO By The Sea - should be voted the global expert on search engine patents. He keeps on top of them and is always breaking solid insights into how the patent applies to the various engines and ways to learn from them.
"A trio of patent applications from Google look at estimating the likelihood that an advertisement is a good one, in a method that goes beyond counting click-through-rates (CTR)." he blogged.
The blog is one worth reading and if you have any insights or comments let's discuss them here.