New Player In town (Canvas)
It look like we have a new player in town - in my opinion it will be the next RIA generation.
The canvas element is part of HTML5 and allows for dynamic scriptable rendering of bitmap images. you can read about it in here. If you'll look around you'll notice that new Canvas UI and Game frameworks emerging.
True, it's not there - we do not have all we need to build a standard application but as I can see it the existing frameworks are far more advanced then JavaFX (correct me if I'm wrong) see the below List of examples to existing JS frameworks for Canvas.
The only one thing you can claim as a big con is the browser's support. The Canvas apply for those browsers which supports HTML 5.0 - but this is temporary since the following project leads us to the answer:
Excanvas -Modern browsers like Firefox, Safari, Chrome and Opera support the HTML5 canvas tag to allow 2D command-based drawing. ExplorerCanvas brings the same functionality to Internet Explorer. To use, web developers only need to include a single script tag in their existing web pages
In here you can find some more framewroks.
In my opinion, From all of the above framework Mochaui is the most robust framework.
We will probably see more traffic and lots of action in this area.