JavaFX seems cool but the deployment possibilities are weak:
* On the desktop computers that have an updated JRE can run JavaFX applet (but OpenJDK on Ubuntu 10.04 just dies)
* There doesn't seem to be any phone advertised as supporting JavaFX. The HTC Diamond that Sun was giving away at JavaONE 2009 was running Windows Mobile. Not exactly a market leader.

To be able to deploy on a lot of older hardware it seems safer to target the old J2ME and use a 
compatibility library to port the software to modern hardware ([J2ME library])

On mobile hardware HTML5 provides better deployment (iPhone + Android + new Blackberrys etc.). I wonder if GWT could be used to convert non-GWT java code (say a little game using J2ME) to Javascript. There are [restrictions|http://code.google.com/webtoolkit/doc/latest/DevGuideCodingBasicsCompatibility.html] for the Java to Javascript.

Still JavaFX has cool features:
* easily reuse Java code
* cross-platform GUIs with great graphics
* declarative approach
* properties, events