JavaFX: Open source or not?

Will JavaFX, Sun's new rich Internet applications platform, be open source? That's certainly the impression that many took away from JavaOne. On his blog, JavaFX booster Julian Exenberger says, "If Sun makes good on it's promises, JavaFX will be the only fully open source RIA with a fully open source runtime. It will even have open source development tools."

But Simon Brocklehurst took a closer look at those promises and catches this verbage from the JavaFX FAQ on Sun's site:

"JavaFX technology is very early in its development. The JavaFX Script language, currently being developed with the community's help (see OpenJFX project), will have a grammar and syntax that are open source. Some parts of the language are already open source. The JavaFX compiler, runtime engine, player, and tools currently under development are not expected to be open source. You can participate in the OpenJFX Compiler Project, which focuses on creating a JavaFX compiler to translate JavaFX scripts into JVM class files (bytecode). This compiler will leverage and extend the JDK's javac compiler capabilities."

All modern software is made up of innumerable modules and components, so the debate as to how many of those need to be open source for the entire package to be considered open source is probably philosophical at this point. Still, it seems that Sun's New New Thing could be at the center of yet another tedious open source battle.