This is a funny thing. People seem very assured that Google will stay on top for a looong time, that their search is just too good and the simplicity of the interface and their goodness and bla bla bla. I think MS might change the search landscape quite quickly. The reason is that people go to the search engine that delivers the best results, period. That's the reason Google rules and that's what it takes to become the global search king. The Best Search Results!
Now if you think it's hard to deliver better search results than Google you're right, it is. BUT, there are many promising ways to improve search and I find user context and user knowledge the two most interesting. If you know what context the user is in when she performs a search you can filter out the stuff that doesn't belong and if you know how much the user knows about a certain topic there are many ways to sort the results that will enhance the results for the user. So delivering better search results is not impossible and I'm sure MS will think of some things that Google hasn't thought about. I don't like the thought but I won't go into denial just because the truth is a bit uncomfortable.

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