Just found this off the latest edition of Autospies... a 6-series Spy Shot, and I noticed something rather peculiar.
Look at the bumper. Seems like a taped up M bumper with somewhat of an M-esque shape. But look at that shiny silver thing below the kidney grilles. While many may yet again pass it as an intercooler, don't you think there are too few passes for it to be trully effective. Its probably a front mounted oil cooler as others have suggested. So the likelihood of BMW going a blower route on the M5/M6 now seems to be quite slim.
Just my thoughts. What do you think??