I have to say, I agree with everything Dion Hinchcliffe says here.
Spreadsheets, Hypercard, Wiki ... three of the applications that have most succesfully created a gradient between "user" and "developer". New innovation will come from the "edge" experts in these, and other software which takes its lead from them.
When I wrote that innovation came from developers and couldn't come from users, what I was really thinking of was "passive users", who couldn't or wouldn't understand what the deep model of what was going on in their software. Those that can understand what it's really doing, and can use this knowledge to help pioneer new ways of use, may very well be innovators.