I think it's missing something to be honest.
The cars are white, but the meter has averaged the scene and they've come out a little grey - I would think this could be easily adjusted in PS.
I think the main problem is in the composition. There's a big gap between the cars which, because of their alignment, draws the eye to the bollard and the house/tree in the background.
Personally I would probably have gone for off-setting the cars and getting in tighter to reduce the amount of black sky and ground, but keeping the focus on the vehicles. Something perhaps more like this:
http://www.sandsmuseum.com/cars/elise/information/press/magazine/magazine2004/latimes1.jpg
One thing which is quite helpful to think about when taking a car shot is the roofline - follow it with your eyes and make sure that there's nothing conflicting with the lines of the cars.
Also, I'd probably turn the foglights off on the Hyundai (or buy some for the Scoobie!)
I'd say to try and find a carpark with nearer to infinity background for this kind of shot. Out of town shopping centres are a favourite as they're normally quite well lit and very large.
I like the blue lights btw!
Rob