OK, found some numbers to justify my theory that this new (M) coupe just looks too long.
If we assume the F32/F82 share the same wheelbase as the F30, it would have a wheelbase of 2810mm, i.e. 110.6". The E90/90 has a wheelbase of 108.7", and the E63 6er had a wheelbase of 109.5"! So the new coupe will likely have a full inch longer wheel base than the big old 650i. That is crazy. No wonder it seems so big and looks like a 6-series going around the track.
I'm sure it will be a good looking car, but I don't think I want a coupe much bigger than my E92.