Not sure why. My guess is that some executives at BP and BMW didn't agree with each other, and BP lost their long-standing deal with BMW.
It'll be interesting to see if they still give out 5w30 at the dealer, or if they'll change viscosity grades. I'm guessing that they won't.
I wouldn't be surprised if Shell Helix ends up being the new OEM formula.
http://www.shell.com/global/products...tra/ultra.html