NYT has an article (by Saul Hansell) comparing features offered by Google and Yahoo and their acceptance by people. The basic question is:
Do Internet users prefer services that are consistent and predictable, like those offered by Yahoo, or are they more interested in Google’s wow factor? These two approaches define a pivotal front in the battle for online loyalty between the major players in the Internet search business.
I know I go to Google Maps for fun exploration, but go to Yahoo Maps when I need to do something serious.