Submissions have to be either new or interesting. There are a lot of submissions that aren't necessarily new, but still have interest for this community judging by the votes. An example that's on the frontpage right now is this: http://news.ycombinator.com/item?id=1051493 which is from 2007.
Personally I think the linked article is interesting because of some of the truths hiding between the lines such as this one: "But the main reason that any programmer learning any new language thinks the new language is SO much better than the old one is because he’s a better programmer now! You look back at your old ugly PHP code, compared to your new beautiful Ruby code, and think, “God that PHP is ugly!” But don’t forget you wrote that PHP years ago and are unfairly discriminating against it now."
He also learnt new approaches from Ruby - reminds me of esr's "learn lisp to improve your coding, not necessarily to use it".
It also seems he became something of a coding god, especially in his domain, able to create frameworks he needed - on demand. It's impressive to be able to create those tools, but even more impressive to realize what you need - and then for the tools to be both actually useful and usable. Generally, it's said to be a bad idea to write your own tools - unless you can (i.e. have the ability), says Alan Kay, because then you can create just the right tool for the job. Though perhaps no one else quite understands them, not being gods, and so they need to rewrite in aspx.
I like his non-coding observation. GIRLFRIENDS: THE NEW ONE IS BETTER BECAUSE * YOU * ARE BETTER
He intimately understood exactly what his application needed, and had working code to start from. I think that was what enabled him to build the tools he needed.
Personally I think the linked article is interesting because of some of the truths hiding between the lines such as this one: "But the main reason that any programmer learning any new language thinks the new language is SO much better than the old one is because he’s a better programmer now! You look back at your old ugly PHP code, compared to your new beautiful Ruby code, and think, “God that PHP is ugly!” But don’t forget you wrote that PHP years ago and are unfairly discriminating against it now."