It seems like still-quality video will be the future for digital - ie being able to isolate a single frame from video and have it be of as good quality as a still shot. The other thing coming in sensor design is much more efficient light capture, which means you'll be able to shoot at ISO 100,000 with ISO 100 image quality. So it seems there's plenty on the digital horizon to make people buy and buy again.
My guess (hope?) is film will be around for a while. My reasoning is that as digital continues to evolve it becomes less and less like traditional photography. In my opinion it is already a medium unto itself, rather than a digital version of film photography. So perhaps there will be room for both, and a continuing market for 35mm film. The question though is will you be able to buy a camera? What will film users do when their cameras eventually die on them? Will Nikon make the F6 for much longer? I doubt it. For crying out loud, they don't even build their new lenses with aperture rings. So, while it seems people are still buying alot of film from Ilford, will a lack of camera availability eventually force people to give up on film? Or will a continuing demand for film drive one or two manufacturers to make cameras? Will anyone make SLRs, or will all film users be forced into the rangefinder niche? Sad stuff.