Agree with Luigi. Moreover, JavaFX 2.0 is a Java API like any other, obviating the need to learn a different syntax.
While using bindings in JavaFX 2.0 is at present rather verbose when compared to the terse bindings of JavaFX Script, the introduction of closures in Java 8 will alleviate that.
Possibly the greatest advantage JavaFX offers over the other UI packages (Swing, AWT) is the ability to customize the UI via CSS, supporting both node-specific and inherited styles. On the down side (IMHO), the API is high level in the extreme, making it difficult to customize via inheritance.
Till date, the single most disturbing 'feature' of FX that has come to my attention is that
showing a modal dialog doesn't block the thread of execution -- and the FX team maintains that the behavior is "by design"
This is contrary to modality concepts not only in Swing but in other, non-related visual platforms such as VB and VFP.