JavaFX is the latest Rich Internet Applications technology to hit the market. It was first announced by Sun microsystems in 2007 in the JavaOne conference and it seems the javaFX sdk would be out by late this year. Already a beta javaFX script plugin is available for netbeans.
Actually the first RIA technology was a java technology. It is none other than Java applets. Applets never gained any popularity and the word RIA was yet to be suggested. It was Macromedia that first came up with the word RIA.
The aim of Sun is to offer a family of products that could be used to develop Rich Internet Applications across multiple devices. JavaFX would consist of two technologies called JavaFX Script and javaFX Mobile.
So it looks like it would be a battle between Adobes head first start in the RIA technology against the marketing power of the Microsoft against the popularity of the java language.