Are you a Pentax SLR user? If not did you have a look at the Canon 10D and 300D and nikon D70?
I don't own the *ist D but have read reviews on it. It is praised for the small and light body, big viewfinder, good performance at high ISOs. The major complains are soft images straight from camera, incompatibility with older lenses, small directional pad, difficult to take CF card out, inconsistent flash metering. If you can wait, Pentax is likely to announce another DSLR at Photokina.