Both are very cool. The two brands are both coming out with cars that are of the future at the moment. Another brand that is doing cool things like this is Volvo surprisingly enough. I just love the tailights on their XC Coupe Concept.
I think that the belt line should stay. Reports say the NX is going to keep a lot of the aggressive styling. Not sure how much, but I think people would be upset if they dumbed down the design a lot.