I'm sure he is concentrating on his startup. What's wrong if he took a short break to write Uncov article?
So what if his idea has already implemented? Google's idea had been implemented by others as well. Just that Google does it better. It's possible that his startup might do it better.
I kind of agree with you that he has no solid data on these "dumb buyers" but I think the word "acquired" should be swapped with "invested". There are a lot of web 2.0 companies that don't have strong revenue but got a lot of money via investment. Let me ask you back, can you give example of web 2.0 companies with strong revenue record?
The best deal I've seen so far was Flickr's 30-40 million dollars. The rest seem to be over valued.
What's wrong with Joost and 100 employees? If Joost really needs 100 employees, be it. They have a solid product compare to most of YCombinator companies out there.
By the way, out of 50 YComb companies out there, I only use Reddit.