Let us not forget about the new breed of Search Engines: the personalized SEs. New SEs like amazon's A9 are poping out every day offering people search results not only based on what they are searching but also offers results based on things they search before. I believe that amazon's A9 will become a player simply because of Amazon's reach and the options given to A9 users.

It is nice to get lots and lots of search results like in Google but when people have to go 6-10 pages deep to find good content pages, that is a saturation that will have people go to SEs like A9. I truly think the future of search engines will go that way.