When I first was going to get chickens, I was really worried about the smell and the noise. I live in Brooklyn, NY, and don't get along with neighbors on one side, so this was really important.
I asked a chicken-keeping friend how often she cleaned out the coop. She is one of those incredibly neat, clean, organized people. She thought for a second and then said, "I guess I clean it about.... once... a..." I was sure she was going to say once a week or even once a day. But no: "About once a year, and I never noticed it smelling bad."
I clean my coop out whenever I start fussing with my compost and want to put the poop in the compost (It makes the compost turn faster). It doesn't smell!! Our run is roofed, so it stays dry, and I really think that's the ticket.
I constantly find BYC a great resource, but I started out with MyPetChicken.com, and found they were great for choosing breeds.