With the release of Inkscape 0.47, Inkscape now offers its users to save their work as JavaFX *.fx files. This is how it works for you.
Create a graphic in Inkscape for example:

Choose File -> Save As… -> Select file type as JavaFX *.fx
The file name you have chosen for your JavaFX file is the name of the JavaFX class. We named our file MyShape.fx
So in a JavaFX Project you can call new MyShape and your graphic should appear.

Unfortunately there were three bugs that we encountered in this simple example.
Number one, the text of our Inkscape drawing does not show up in the JavaFX export (Inkscape Bug 489364).
Number two, in the create Method of the JavaFX export file a method named path4117-5() is called (Inkscape Bug 439270). This is not only incorrect syntax but the method does not exist. It was called path4117_5() and changes had to be made to the JavaFX file.
And number three, as you can see the stroke width of the line is not the same. Going into the code you can see that the width is set to 0.0 in Inkscape’s JavaFX file, when in fact it should be set to 6.0. (I filed bug 497416).
If you would like to avoid names such as path4117 etc. in your JavaFX files, select any one of your objects in Inkscape, press the right mouse button and select “object properties”. Here you can change the Id to something that is easier to remember.
There are of course more things to discover in collaboratively working with JavaFX and Inkscape, some of which we might focus on in the near future.
While these three bugs are unfortunate, they will probably be easy to resolve. Let us also not forget, that JavaFX support is new to Inkscape. What counts for now is that it is great that Inkscape offers an open source alternative to creating graphics for JavaFX.