Can anyone quote the opt-in language that Microsoft uses for the Bing toolbar? Although I'm still not sure about whether there's a difference, I think there's a clear distinction between watching users of your site and taking action based on that (Google and search link clicks) and watching users of your toolbar everywhere on the internet and taking action based on that. (And that distinction is as clearly drawn between google.com and the Google toolbar.)

I've always felt that, yes, Google collects a lot of personal data, but they're up front about the collection and they give me good value in return - which is sadly not my general expectation of data collection.