The Bad News: hidapi (for bfgminer) looks to be a bust on ARM architectures, I have tried it on several different device types with varying results, anything from crashes to unstability. Deffinatly nothing you would want to trust your mining gear to.
3 days solid mining here on the BBB with hidapi on Debian. Mining like a champ with two IceFurys, and two Jalapenos.
Currently just using MinePeon to proxy my ASICMiners, Pi is plugged in to the USB port on the back of my Airport Extreme. Working like a little champ, though the heat from the Airport is pushing the Pi up to 58-60C, even with heat sinks on the Pi's chips.
