The new buzz word is definitely "Web Applications". Unfortunately, recent publications on this topic are extremely confusing. Web applications require a massive deployment of JavaScript, but everybody skilfully pretends they don't. Besides, I haven't yet found out what Web applications are because no one has bothered to define them.
Are Web Applications here to stay, or are they just another hype?
See Dave Shea's Web Apps are Hot for an overview of recent publications. See also Joel Spolski's perceptive How Microsoft Lost the API War article.