i think that the proper way to think about it is that this "4 series coupe" is a completely different car than the current 3 coupe. if you want a coupe from BMW, it'll be a 2, 4 or 6. i bet the 2 will be a lot more like the current 3 series. this 4 will be priced at 50k+ most likely and compete with the a5. i think its a good marketing move for BMW. it simplifies things a lot. 1,3,5,7 sedans. 2,4,6 coupes.
and besides saying that it looks like an a5 is a good thing in my opinion. the a5 as a beautiful car...