this is currently visible on http://www.google.co.uk if you go there with Internet Explorer..

http://i38.tinypic.com/sbk2vs.jpg

This is something that Google is doing for some time now. I always have this when I start Internet Explorer.

Instead of promoting the toolbar, Google now promotes Chrome.

Yes, I've seen the Chrome promotion in my IE for a looooong time now.

http://alteregozi.com/2009/04/18/google-converts-the-converted/