Ok, here's the deal. I go to yahoo.com and it's filled with ads, a bazillion links I don't need/want, and there is a search box buried up top, hiding in the midst of the noise and clutter. Searching is not the first thing my eye is drawn to on that page.
When I goto google.com I see just a search box and 5 places to search from. Searching is the only thing to do on that page.
Now, where you gonna go when you need to find something? A circus, or a search engine?