Regarding realtime stuff there's a project out there to implement the Ethernet AVB (audio/video bridging) standard on BeagleBone using PTP (precision time protocol) for synchronization.
Some of the older network synchronized transports like CobraNet and Dante might also be interesting for anyone wanting to learn more about this stuff.
I don't know yet. When the time comes to implementation we'll look whether we can re-use either the code or ideas or maybe instead integrate Roc into GStreamer as a network transport (actually I was thinking about it already and there is an item in the roadmap for it).