I'd like to make the sheevaplug port available soon. We've hit a bug in the latest 5c or 5l and I'd like to wait for that to be fixed first. The initial port was not done on a stock kernel, and adapting it to a stock kernel produced a less reliable port (probably my fault). I think I've just fixed the cause of the unreliability but need to test it.
The current port only drives the gigabit ethernet inteface and serial console, and will be more useful once USB and access to flash memory are working.