Check out http://tech.memeorandum.com/060501/p8#a060501p8
In this article I found this, "The new browser includes a search box in the upper-right corner that is typically set up to send users to Microsoft's MSN search service. Google contends that this puts Microsoft in a position to unfairly grab Web traffic and advertising dollars from its competitors."
I also found this,
"The focus of Google's concern is a slender box in the corner of the browser window that allows users to start a search directly instead of first going to the Web site of a search engine like Google, Yahoo or MSN. Typing a query and hitting "Enter" immediately brings up a page of results from a designated search engine."
hmm i am really pissed off on seeing Google's reaction. Why? Because just couple of weeks back I bought a new Dell Inspiron 1505 notebook. I was really shocked to see that Google search box was by DEFAULT added to the Internet Explorer.
Now if the same thing is done by Microsoft on its (IE 7) own Browser to set MSN as their default search engine (that too configurable) google is getting paranoid .. really funny :)