That's a Mercedes being driven by Zach Galifianakis for a scene
in the upcoming Hangover III. You can watch footage below.
Well, now we get to see what all the fuss was about: below is a clip released by Starzuncut of what was shot over the weekend - apparently Alan (played by Zach Galifianakis) is hauling a giraffe in an animal trailer when he crashes into a semi truck, causing the giraffe to get loose, with hilarity ensuing.
In today's Orange County Register, Warner Brothers took out full-page ad, thanking O.C. residents for their patience and acknowledging, "We know that traffic disruptions can be unpleasant and that many of you, particularly the communities of Irvine, Newport Beach and Costa Mesa were impacted by the closure of a section of SR-73. Your understanding is greatly appreciated and went a long way to making this a successful shoot."