Connections are as such... Left and Right servos on pin0 and pin1 (respectively). The XBee (Rx and Tx) is connected on pins 6 and 7 (respectively). I also have the ProtoBoard accessories pack attached, but not currently using it.
The code running on the propeller was written by Mike Green from the Parallax Forums. In order to control the bot over XBee, I used a spare Logitech Gamepad I had laying around. So I wrote Linux Control software [zipped source files, and build shell script] that takes the Joystick port input and transforms it into servo pulse widths and sends the commands to the XBee over the serial port device.
Future plans for the bot in the near term include adding IR for wall detection, writing my own "OS" for the bot's MCU (prop).