I'm sorry if this is rude, but I downvoted you. I did that because you didn't bother to read the article, but you bothered to comment.
It's just isn't that simple. His argument for the MacBook Air is that it's in the same form factor, while having incredible battery life and being more powerful computationally. Plus, throw in OS X and you have a deal. In a way Air is netbook inspired in terms of the form factor, and the it killed the netbook by making the point that you could still pack in impressive features into a form factor that small by conventional standards, while having a decent profit margin.
In the article, the author makes the point that what really killed the netbook was portable computing (in the form of smart phones and tablets) that packed the same punch and was more intuitive, while maintaining a good enough profit margin for hardware manufacturers to stampede in order to get into the segment.
That said, I have a netbook, an Acer Aspire One, and it runs Ubuntu 10.10 with a grin and is quite awesome once you get used to the tiny keyboard...
Besides, I really do think that no one is taking real advantage of modern computing and you can still write Ruby code on Pentium 2 era PC once you flash it and boil it down to the basics. I think that if someone is dedicated then even a dumb terminal is enough to write code, why do you need that new found computational power? This really is an honest question.