Interestingly enough, Twitter was first on the scene, as the commuter Joe Marshall (@larfo) snapped this Twitpic of the Bay Bridge debris. The image, taken about two hours ago, clearly depicts the San Francisco Bay Bridge with what appears to be cables down and bridge mass spewed everywhere.
The Chronicle reports:
"A chunk of steel lay in the middle of the far left lane of the upper deck and an object that appeared to be a cable was on a Ryder truck dangling from the side of the span.
Authorities have not said how long the closure will last."
While this is certainly not the first time that a Twitter user tweeted breaking news before mainstream media outlets — there's plenty of incidents like the Jakarta bombings and Hudson plane crash to reference — it certainly serves as another telling example of the power of Twitter as a communication platform.