There might also be another effect. Both Microsoft's search (under the MSN name) and Yahoo's existed before Google's. Google came along and really beat all th

There might also be another effect. Both Microsoft's search (under the MSN name) and Yahoo's existed before Google's. Google came along and really beat all the search engines that exited in terms of result quality. Microsoft and Yahoo have since upgraded their algorithms and gotten a lot better. However, people still associate the two as being the poor engines compared to Google's that they used to be. People's subjective evaluation of quality isn't just based on current results, but experiences they've had which might no longer apply due to changes in the product. There's no reason to include Yahoo search capabilities from 6 years ago in one's evaluation of Yahoo's results, but that's how people's minds operate. I think that's why Microsoft desperately wants to rebrand their engine (over and over) so that people will think it's something new that they should evaluate for the first time rather than the pre-Google product that they found inferior to Google.