Technical content tends to be more picky about layout etc than prose, which can be an issue for e-readers. Also some technical books suffer from the lack of ability to quickly browse and jump from one page to another.
Very good point about jumping around in technical books. I rarely read any tech books for this reason. eBooks are better suited for casual reading which is done front to back. Tech/reference books suffer on eReaders due to poor navigation and insufficient linking.
