JavaFX with it's binding seems great technology for building UI layer, replacing PHP+AJAX, but are there any frameworks for building database forms applications with JavaFX, or it is meant to write everything from scratch?
You should give a try to some recent libraries :
JRebirth Application Framework to structure your whole application http://www.jrebirth.org
FXForm to manage form http://dooapp.github.com/FXForm2/
DataFX to manage complex tables etc.. http://www.javafxdata.org
You can find more tools at http://www.oracle.com/technetwork/java/javafx/community/3rd-party-1844355.html