I don't know of any dates, maybe Dave will chime in on that one. If you would like to start sinking your teeth into it, the following interfaces will be supported (to varying degrees):
https://www.kernel.org/doc/Documentatio ... fs-bus-iio
https://archive.fosdem.org/2012/schedul ... system.pdf
http://wiki.analog.com/software/linux/d ... trig-sysfs
Dave is also working on a python library, which will be used for the mission.
The LED matrix will come up as a framebuffer (8x8 RGB565) and the joystick will be a normal input device.
While developing, we're relying on RTIMULib a fair bit, since it's easy to get started with and great for demos, but the plan is to write IIO drivers to keep things standard and avoid userland drivers.
It's really up to you how you want to talk to these devices, high level libraries, kernel drivers or poke the registers directly.