I'd say calibration belongs into some framework/config plugin/whatever, but not in every single application.

Also, if you like accelerometers, get yourself a wii motion+. That's what i call precise inertial sensorics. My tilt dongle is stone age technology compared to that and so are all the cell phone things. The wii sensors reference coordinates are rock solid over several minutes of constant movent at all six degrees of freedom which is pretty cool for his kind of technology.