First off, I hope that everyone involved in ok. Everything else can be fixed or replaced. Ultimately, the car did what it was designed to do...protect you and any passengers you might be carrying.
Having just been in an accident myself, I feel for you. I am not sure if it's repairable or not, but do research on various dealerships/bodyshops your insurance company deals with. Make sure you get new, all OEM replacement body parts. Some companies will try and get you to go with parts from a junkyard or from 3rd party manufacturers. Also, make sure that the bodyshop offers a lifetime guarantee on the repairs. Make sure they are experienced in performing repairs on BMWs, the materials BMW uses in the cars, and that the shop is calling the shots on what needs to be done...not the insurance company. Finally, try and deal with a shop that the insurance company works with (and pays directly). This way you don't have to shell out cash for the repair, then wait for the reimbursement.
As an example, my (then future) Mother in law backed into one of my previous cars. The bodyshop wanted to remove the rear side window (coupe) to do a better job with the paint. Her insurance company wanted them to just mask the window off.
Also, be sure that they have the equipment to inspect and repair the frame (if needed)
Good luck to you,
2013 BMW 550i M-Sport - ZCW, ZDH, ZEC, ZMP, 2TB
2011 Ford F350 Crew Cab Short bed
2006 BMW 330i Premium, Sport, Automatic, Comfort Access
2004 Lexus GS 430, 2001 GMC Yukon, 1999 Pontiac Grand Prix GTP, 1997 Ford Thunderbird V-8
Last edited by Stonehauler; 10-02-2012 at 10:03 AM.