Java Media
This blog post by Chris Adamson is a good read. Even got a line or two about Java FX in it.
This guy has been doing a lot (well, more than you) of Quicktime code and understand the boring problems. My addition to his words is that any new audio/video support is not really that helpfull without a new media Applet system or first class Web Start support. The current Applet loader just crashes Firefox over and over again. They have to rethink the class loading system and cut down the number of file reads on the disk. Starting an Applet today is like starting Photoshop.
Web Start is looking better and better, but is still a bitch to debug and still slightly retarded when in sandbox mode.