There's a big difference between invention and innovation. Both are important, but we do less and less of the former. The idea of a mouse before PARC must have seemed a little crazy, whereas the idea of the iPhone before 2008 seems a little inevitable.

Alan Kay's recent talk "The Future Doesn't Have To Be Incremental" goes over this yin and yang of the two 'i' words of our industry with authority. Worth a watch.