The simple fact is that one mega search engine simply isn't enough. We need a social search, a big brand search, a mom n'pop search and goodness knows what else. The only way to achieve this is to wean the public off the idea that search means Google but if this doesn't happen I reckon the web will soon be looking like the High Streets here in the UK; once full of individuality, character and variety but now dominated by big anonymous chains.
Could Google split into different divisions to meet this need I wonder? Would they want to?