I have a degree of sympathy with TightSlot's view. I'll bet that a fair proportion of laptops used by passenger in-flight have their wireless enabled (possibly by user ignorance), and even the newer generation iPods (e.g. Touch) have wireless internet built in, and thus are capable of "transmitting". But no one really yet thinks about insisting these devices are kept off throughout a flight. What next - iPods banned on long flights? Don't think that'll go down too well, but how does any layman really determine which transmit and which don't? Rules need to be sensible, not rediculous, in order to increase passenger compliance, but devices keep getting more sophisticated. The only realistic ways to solve the issue are (a) to ban ALL portable electronic devices in flight, including laptops and music players, or (b) sort out carefully what devices really mess with aeroplane systems, strictly enforce a ban on those, and let others like GPSs, laptops and iPods be used.
FWIW, I find it rediculous that a device that can actually be used for navigation in an aircraft - a handheld GPS device - without additional aircraft certification, cannot be used in an aircraft! That's not to say I wouldn't switch one off if I had one - just that in respect of GPS the rules are non-sensical.
A