Out of curiosity, what sort of things would bring down a site as big as Facebook like this? I'm sure they have many checks, balances, and methods of ensuring a code change wouldn't impact the site (to this extent) - and they are distributed across many data-centers, so I wouldn't think that would cause it to go down.
Looks like it's back up, we can all be social again.
"Again" seems to be a quite loaded headline. I don't use facebook, is this a common occurence?
All things considered, it's remarkably rare that the general consumer facing parts are down.