Polling vs. pushing (ou HTTP vs. XMPP)

Lorsque c'est Roy T. Fielding himself qui monte au créneau ça fait mal :

this FriendFeed example is ridiculous. It took me less than 30 seconds to design a better solution using nothing more than HTTP, and that while sitting in the middle of a conference session.

Les solutions envisagées sont intéressantes et j'aime beaucoup l'image centralisation vs. peer-to-peer.