I recently read an article in Business Week, describing the birth of “Real-Time Web”, and a flood of investments into the area. The concept is pioneered by Facebook and Twitter, where the action that happens “now”.
Today I heard about PubSubHubbub from Google (try pronouncing it, I’ll wait). It allows you to use a hub for pushing updates in real-time. The protocol is based on Atom and RSS, and is completely open.
Right now there are no good frameworks for real-time web, based on events communicated from the server to the client, rather than the other way around. PubSubHubbub is a good intermediary between the old concepts of dynamic web and the real-time web. I expect to see more general purpose frameworks to appear that support real-time web concepts to appear soon as the paradigm shifts in that direction.