Looking through the code, there is an asynchronous connection to facebook (connect.facebook.net/en_US/all.js) to check your online status and stuff. That's in order to present you with the right set of FB options (e.g., like/send, etc.). If that connection is blocked it may appear as an intermediate url in your history.
That's all Greek geek to me.... Thanks for the explanation though!DefSent from my MB860 using Tapatalk 2