Propools - 5:28 pm on Feb 16, 2011 (gmt 0)

Bing has connected with Facebook to make searching on Bing more social. Together, Bing and Facebook offer you better search results and a more personalized experience with the help of your Facebook friends.

Since Microsoft does have a financial interest in Facebook it's a natural business model "bolt on" extension.

I think Bing has got it going on with this [discoverbing.com]. This isn't a browser extension, it's a business extension.