Living Room design... dark colors in furniture or rug?

I have just gotten a new apartment and am trying to decide options for my living area. It is fairly small and open to the kitchen. I will have black and white photos and more contemporary art on my walls. I want to get a shag rug and a new couch and chairs. Is it better to bring color into the room through the rug or have a black rug and brighter tones in the furniture to make the room look as open as possible.