[BigMacSmallFries]

Automobile mag just stated the horsepower and torque will be approximately 450hp and 406 ft lbs respectively. Check the home page out.

Let's assume the redline is 7900 for now.

Edit:

Since the M5/M6 horsepower and torque is 560 and 500, I imagine the goal of the engineers was 100 less in each category: 460 and 400.

However I imagine BMW M would create horsepower levels that separate the 2, 4, and 6 in a simplified manner. For example:

M6: 560 500 8cyl
M4: 450 400 6cyl
M2: 340 300 4cyl

A scheme like that would make sense and sound plausible to me.