Automaker silent on whether it's CGI or real

Reader with Acrophobia beware: BMW's gone and drifted its new 1 Series M Coupe atop the world's highest helipad.

At least we think they have. The German automaker's been rather quiet about whether the stunt on top of Los Angeles' 73-story U.S. Bank Tower was actually done or if it's all clever computer generation.

The 45-second video's up on YouTube, with little description. We do know it was uploaded by BMW Canada (woot!), but there's no word if the ad was actually spearheaded here.