Matt -- I'll concede that, but I suppose in Google's position they have to be wary of the odd end user that will inadvertently click the wrong button. Heck, they even have a warning for their "Report phishing" system.
This just makes no sense whatsoever. Why would you make a banner promoting a inferior browser? I'll agree it's better for the average user; open source needs to get it's act together for usability and really rethink their target market. But the fact of the matter is simple - IE shouldn't have something like this for the simple fact that it's misleading.
P.S. I have IE6SP1, Maxthon, MyIE2, FF1.5, FF1.5.0.1, Opera and Mozilla Suite installed. Don't tell me i'm biased.