You can be fairly confident there some startups out there founding by 20 somethings, populated by 20 somethings, who think having someone over 30, or certainly over 40, on their team or even in their office would be akin to the plague. They would probably place them in the same camp as their parents.

I totally understand why coders like Agile, hey I like it because hacking code is the fun part :) Its also kind of a good fit for the app store era, where you throw something out there and see if its sticks before you actually develop most of it. Not entirely sure its actually a good way to develop nontrivial software.