First it's the same old 'users first, monetize later', a distinct problem from monetization strategy: it's a failed mindset where every day you're not charging people is a day you're not learning what you can actually get people to pay for, that is, what constitutes your business.
Secondly he doesn't event start addressing the hard problems of Q&A sites:
1) How to keep the quality of answers high. As soon as more people get on the site, the quality will drop unless there is a smart mechanic to prevent it. All he has is assertion that 'You’re answering questions because ...' as if he knew the answer to that question for the next 100k users who aren't early adopters!
2) How to monetize a Q&A site in the face of approaching commoditization, on a scale that warrants investment. Ads? Really?