JavaFX is very useful in a myriad of different situations. One if the common uses for JavaFX would be in a roll where the collection or display of data is very centralized and would not necessitate the complexity of a full scale web or desktop application.
That is not to say that a JavaFX app would not fit into a larger web environment, however I do not see JavaFX as being a replacement for these larger applications.
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com