MIT OpenCourseWare Now Online
I think there may be too much of a tendency by professors to reuse educational materials. This may lead to a degree of standardization and uniformity of the educational experience that could harm progress.
One of the big problems facing the developers of online course materials is just the opposite, that professors are unwilling to use materials developped by someone else. Most have their own strong opinions on how a course should be taught, and so the chances of a prefessor just grabbing someone else's course notes and using them instead of developping thier own are pretty small.
No, I think this is a really good idea and a great effort, for the reasons that others have covered here.