What do you think of it? I think historically BMW has styled side vents very well. The E46 M3's side vent (if that's the correct term) fit the car perfectly. I am inclined to think BMW is just as successful with this new vent on the 4-Series Coupe Concept, but I have read some criticism on other BMW sites online.
Maybe it won't even make production, or maybe it will only be fitted to the inevitable M4 Coupe.