I'm not sure if anyone already posted this, but I saw that the M4 Convertible is now on BMWUSA.com. I'm looking to buy one next year so I can start configuring one now.
Here is the link to the BYO:
http://www.bmwusa.com/standard/conte...modelcode=154m
Here is the link to the main page of the M4 convertible:
http://www.bmwusa.com/standard/conte...E/default.aspx