Zakas, who spent five years as the front-end tech lead for the Yahoo homepage, recently spoke at the March BayJax Meetup group about what he calls Progressive Enhancement 2.0 — offering users the best possible experience given the capabilities of their device. Not the same experience, but the best possible experience. That means progressively enhancing sites according to the device’s (browser’s) capabilities.
Zakas also takes on the common assumption that a web “page” is analogous to the printed page. In fact Zakas argues the web is more like television, which has a similar separation of content and device. In that analogy old browsers are like black and white TVs. No one expects a black and white TV to play HD content, but everyone would be disappointed if you served black and white content to an HD TV. Hence the need for progressive enhancement.