Personally, I regard the underlying problem here is that browser authors seem to feel the need for any kind of automatic search facilities at all.
If I want to search for something on the web, I might go to google's home page, and enter text into the box. Or maybe same with yahoo, whatever. What is so hard about that?
Worst of all is the now very common combined address bar/search. Last thing I want, having mistyped a URL, is for a browser to somehow try and make sense of what is intrinsically garbage and treat it as a search...