Now I'm pretty sure that Google thinks their magic, whatever that might be, will keep people using Google no matter how much crap they shovel onto the search page. Maybe that was true up to a point, but Google is now over the line. A search engine that did two things would get me to at least seriously try it (and nothing has been able to do that for me since Google rolled out in 1998). Here are the two things.
The bonded part is important. I don't think anyone should switch or even think of switching unless the move was irreversible. It has to be that way forever. We could agree to some small amount of advertising on the search results, in the right margin, and clearly labeled. But beyond that, nothing but search results and whitespace.
I've also been using Google since '98, and the only thing about this analysis I don't understand is why Winer is worried about an irreversible move. It is easy to switch search engines! The problem is at this point it is probably very expensive to start them.