I've been searching for it for days with no success. It's not the Vibe "DJ" commercial; it's the most recent one, where the camera is looking in on a black man as he's driving along; as the commerical progresses, you see the guy's friends, girlfriend, wife, pregnant wife, little girl appear in succession on the seat next to him. The music itself is kind of trance/new age/something or other.
It's a really well-done ad, and a really interesting piece of music. I've successfully found the name and artist behind every Pontiac Vibe ad except that one, and that's the only one I'm interested in.
The song is "Breathe," by the band Telepopmusik.