No. Just for visitors that are coming from a specific IP address (their engineers). The only people that would see the bad results are their engineers. But the URL and data that the toolbar gets looks just like any other one.

This is pretty straightforward and I'd be surprised if Google didn't have the infrastructure in pface to do this today (like literally today).

But then their bad results would be outweighed by the hundreds or thousands of other Bing toolbar users doing Bieber searches getting legitimate results fed back to Bing.

I address this later (although probably after you started writing this comment). :-)

OK, I understand what you mean now. :)

And to be clear (if anyone from Google is reading) you don't just want to do 'Justin Bieber' since I suspect a lot of people with the toolbar actually do that search.

Also do things like 'radix-2 fft', something where there is a lot of additional signals (I suspect), yet something that other toolbar members probably aren't searching for. So the toolbar data MS gets is strongly skewed to your results.