i think Google is too mainstream to die. Look at IE6, it's still going strong and it's a bad browser. Google is a fantastic search engine that is mainstream like IE6. It is doubtful that anyone will defeat Google.
Google is to good to be defeated. There is no alternative of google upto now. i dont think even future will have 1
No one can defeat google because of 1 simple reason...
and that is the best thing
I dont think that it is easy to beat google but no one has seen future so anything can happen and maybe a search engine like google can be defeated in future..