Starting on Wednesday at noon (central time), anyone wanting to join Rush Hour should seek out Wolff at Gamertag: twolff321.  There will be one-on-one street races being held to determine placement in the car club.  If you can't get into the game, just be patient - members will be chosen rather quickly, and will then be asked to give up their spots in the lobby so that other people may participate.

Auditions into the club will last approximately an hour, but there will be many more opportunities if this doesn't work out.  Either hunt down Wolff over Xbox Live, or watch this page for updated playing opportunities.