My profiles:
With Laszlo's new business model built on top of an open-source platform, we are now in a position to make the presentation server an optional component of a Laszlo deployment. Sometime over the next few months, we'll release a build that allows you to compile LZX files on a developer's machine, and post the resulting SWF to a Web server. The SWF in the browser will communicate with XML and media sources directly, with no intervening presentation (proxy) server.[...]
We're expecting that serverless deployment, coupled with open source, will go a long way toward making it easier to deploy rich Internet applications, particularly at high scale.
Temkin also lists limitations of the Flash Player 5.0 as historical reasons that made a presentation server necessary in the first place. Removing this server dependency in production environments should not only help Lazslo on the high end, but it could also contribute to making RIAs more accessible to small businesses. I don't believe in a web where big companies would offer snappy, super-interactive online applications while moms-and-pops would be stuck in FrontPage land. Think about "application syndication," a phrase that has been used for at least six years but that I still don't see it happening much (public examples welcome, if you know any). The first generation players collapsed under their own weight and hopefully easier deployment will help the market get there.
01/29/05 update: I should have linked to this conversation started by iteration two, and it seems I had not paid attention to a huge number of players in this space:
Interesting datapoints: Flash player penetration by version and region, DiamondCluster white paper about rich clients (PDF), Serving Client-Side Applications.
04/22/05 update: Luke Wroblewski has lots of good stuff including Web Application Solutions: A Designer's Guide (PDF).