JavaFX 2 is a great technology. It’s so easy to develop beautiful apps with FXML and CSS. But unforunatly – in contrast to Swing – there is no support for the native look and feel for Windows, Mac and Linux. So if you write a JavaFX 2 app it looks like a JavaFX 2 app. But many user – especially Mac users – want to have Mac OS X apps which look and feel like Mac OS X apps.
So in my opinion it’s very important to deliver JavaFX 2 skins for Windows 7 and Mac OS X 10.7 which look and feel like their native original. Oracle’s goal was to replace Swing by FX2. So in my opinion it’s absolutely necessary to provide the same quality of Look-and-Feels for Windows, Mac and Linux like Swing do! Otherwise JavaFX2 is no real replacement for Swing. Unfortunatly at the moment Oracle has no plans to support this (http://javafx-jira.kenai.com/browse/RT-20299)
I recently started a project to develop native looking skins by CSS. Take a look at my demo application which shows JavaSwing LNF on Mac OS X 10.8 on the left side, and my skin CSS file for JavaFX 2 on the right side.