Robert Scoble points to this interesting search engine experiment. Put in something you are searching for, the search results for three search engines will appear (unlabelled), you pick which one you think is most relavent.
I searched for “Tablet PC” and picked the Google search results.
I probably shouldn’t have searched for “Tablet PC.” I’ve searched for it so many times on a variety of search engines that I fairly sure which results were from Google and which were from MSN. I don’t think this tainted my choice of which results were the most relavent, but it might have.
Also, the test page only lists the top three hits. I generally don’t focus on the top three. I might expect the top one to be an exact match if I’m focusing on something very specific, such as a function name, however, otherwise I tend to scan the first page of hits. I also take into account not just how good the link is, but the text excerpt with it. This is where Google has done very well and I see MSN getting better and better.
So far in the experiment, Google is ahead with Yahoo second and MSN third.