Search naturally tends towards monopoly; nobody wants to navigate to half a dozen separate sites to and parse through the results of each individually to find what they want.

All of them would be ad supported too, thanks to the fact that we in the software industry have conditioned users to expect things for "free" and advertisers would also want to put the bulk of their ad dollars toward the most effective search engine to get the most bang for the buck, again reinforcing the trend toward monopoly.

The only alternative that comes to mind is to make search a government run public utility but, as I'm sure a number of you are thinking rather loudly right now, that comes with its own set of problems.