The conflicting interests involved in building a search engine are a fascinating subject. This is probably a bit deep in the comment tree to start a discussion of it, but it's certainly true that it doesn't do you any good to present wonderful academically vetted search results, if the users don't click on the dang ads.

For the particular search here - yes, you do better than Google, but you don't have a million hungry SEO guys trying to game you. So it's not a fair comparison. If you get as big as Google, it will be a different story. Of course, if you get as big as Google, you might not care :)