Including a .desktop file for javaws to handle MimeType=application/x-java-jnlp-file; would be nice, so webstart "just works". Drop (something like) the attached .desktop file into: /usr/share/applications and include %post scriptlet: update-desktop-database tested here against geogebra.org.
Created attachment 303530 [details] javaws.desktop
Earlier today I committed a .desktop file in the IcedTea repository for this. It will be included in Rawhide soon.
yay!