This doesn't leave Y! many options. They pretty much have to outsource advertising (and
probably search as well) to G in order to stop losing money.
Perhaps they're better off this way. My general feeling is that search is an albatross
around Y!'s neck. With that out of the way, Y! can focus on developing and integrating
creative, useful and fun applications.
As far as M$ goes, in their quest to unseat G as the search/ad king, I do not think that G
can be overtaken by conventional means. Just making better technology won't be enough. They
have to change people's minds about G – they have to make people feel that M$ is
better.