Mmmmm... next Rev. tasty.
If you'd like to take a shot at your own implementation, do some learning at Redfox74's branch on the svn. Look under "MultiSensor".
Maxbotics sensors use either analog or digital outputs. You just connect them to the spare analog or digital pins that are broken out on the IMU shield, and add the necessary code to the Events tab. BTW, ArduCopter will be using Ultrasonic sensors for altitude hold/calibration in the next rev of the code.
Replies
If you'd like to take a shot at your own implementation, do some learning at Redfox74's branch on the svn. Look under "MultiSensor".