That was fast -- mere hours after the FAA said it would allow the use of personal electronics during takeoff and landing, airlines have begun flying under the relaxed rules. Passengers on both Delta and JetBlue aircraft are now free to use their mobile gadgets at nearly every stage of flight. Other major US carriers have yet to officially embrace the lightened regulations, although American Airlines tells Bloomberg that it's already applying for clearance. For the rest, it's likely just a matter of time -- but not too much time, we hope.