Coursera seems to have made a (reasonably) successful business out of it. $1B market cap and almost $200M revenue. Now of course it is not the scale of other SaaS/Enterprise/Social Media outcomes but there is a market here, I think it's all about product vision and creation of new credentialing systems / disrupting the way skills are assessed at a fundamental level. There is clearly a problem with the cost/value ratio with traditional 4 year universities. I also agree selling into the same system is hard.