That's exactly the idea I was going to suggest. Instead of actually upgrading the M5, they might just offer an extra package like they did with the E46 M3.

I agree with many of you that the M5 doesn't need the extra power, it's got more than enough.

One question though, if they decide to offer more power, will the engine displacement remain the same, or will it become a 5.5L engine producing ~550-580hp?