http://www.searchengineguide.com/laycock/003104.html
Some snippets:
....recent findings by comScore show Google's lead in the search market realm diminishing. During that same time period, Yahoo! and Microsoft experienced ratings increases of 2.4% and 2% respectively.
Nate Elliott, an analyst with Jupiter Research explains it this way: "Search engines are more about fashion than they are about technology. Google is cool right now. In another year or two, it's entirely possible that some other engine will be the flavor of the month. These changing tastes have knocked off every leading search engine before Google. There's no reason to think it won't happen to them, too."
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So, what I'm wondering...
Google isn't the only search engine to climb to the top of the rankings and seem unbeatable...how long do you think they'll be able to hold on?
Yahoo! has been a major player with their own engine for a while now...how radically did your search marketing efforts change when they entered the market? Are you still doing anything differently to make sure you are targeting both Google and Yahoo?
Microsoft should be fully entered in the playing field by sometime later this year. What are you doing to make sure your site/business has a presence in the Microsoft search results?