I think there is still a lot of room to disrupt education in the US, and the unfortunate lesson of Udacity is that there really isn't a market for sub-academic degree granted by for-profit institutions.

I agree that the educational platform is really the way to innovate: community based learning, interactive platforms, and social goal setting are all possibilities that could help people leverage internet connectivity to learn. We've yet to see a truly "mobile first" educational platform, which connects experts to the knowledge gaps of the population "on demand". Maybe someday I'll fix a flat tire by taking a quick course, or connecting directly with an expert to walk me through the process!