Looking at Alpha RC1 I see regular ArduPilot telemetry isn´t in just yet but there is a way to route the USB console port to the Telemetry port instead so that hooking up XBee to that port will allow a wireless serial port instead of USB cable. Very neat. For Alpha this makes it possible to use XBee for Configurator access to the ArduCopter in a wireless way both for stationary calibration work and in flight (impressive demonstrator to show off how you can present live sensor data while in flight).
In addition to hooking up the serial lines from the Telemetry port to the XBee serial port board you set a #define in the source and recompile so that the console port goes via the Telemetry port instead of the USB port.
In Alpha_RC1, to use the Telemetry port as console you add the line
anywhere prior to the line
in the sketch "Arducopter_alpha_RC1",
then recompile and upload new firmware.
On thursday I´ll add a post on how I paired up a couple of XBees using USB adapters
and finally added an XBee in the ArduCopter. Tomorrow is a tough day where I try to pass a skills assessment for a demanding consultant mission so I´ll be totally offline.