We managed to get our hands into a Raspberry Pi 3 and decided to give APM a try with it using the PXFmini.
A Raspbian OS image with everything ready for the PXFmini is available at http://erlerobotics.com/docs/Artificial_Brains_and_Autopilots/Operating_System_images/Debian.html.
Full report of the experience available at http://diydrones.com/profiles/blogs/first-flight-with-the-raspberry-pi-312.
Nice, are you guys going full steam ahead with the PXFmini going forward or are you also gonna make a Erle Brain 3 autopilot based on the RPI 3?
When I've learned enough about flying and building drones, that's one project I'd like to do myself. You could have a good AI on that Pi. Plus there's better cards out there to boot.