I know you can get a very day-like shot if you let a nighttime exposure go long enough - but the problem with that is that in a setting like this, it just looks like an overcast day.
I would have rated this higher had the angle of the skyline been straight - I find that the picture drops to the right which is distracting. I like the colour and the mood of the subjects though.
I think that cropping the right hand portion of the frame would have enhanced this shot. A square format would also have helped I think. Overall a nice shot, good tones for the subject, and good exposure.