Here's a depressing bit of research: last year camera phones outsold digital cameras 4:1.
I saw some evidence last weekend at a car show. There seemed to be as many people taking photographs with their cell phones as with digital cameras.
I do believe, however, that the statistic is a bit misleading. When I buy a digital camera, I buy it to take photographs. When I buy a cell phone with a built-in camera, I buy it to talk. The added camera feature is an extra that I might (or might not) use.