I have had some really good experiences searching on Yahoo for scientific information. I recently broke my foot, a break which has a special name. I searched and searched on Google for useful information about this particular break, ways to heal faster (without buying a bunch of crap from affiliate sites), and personal experiences with this type of break (from forums, etc). I eventually gave up on Google and went to Yahoo where I found twice as many useful resources/pages.
Sure, I am very angry with the way Yahoo has banned my site and refuses to listen to my requests for reinclusion; maybe one day they will remove the penalty. And while I would like to see them index and update a bit faster, their scoring algorithms seem to produce more relevance in my experience than G and M.