I had a D100 for 8 years prior to getting the D7K in 2/2011. Big difference in how they work and picture quality. Initially, I was going to keep mine as a second body, but after seeing the difference in picture quality, I sold it. It's tough enough learning the D7000, much less two cameras from different digital generations.
Jim Singler D7K with a bunch of lenses and other assorted stuff