On the issue of mobile phones in flight, Myth-busters did a test with mobile phones vs an airplane...
Their results was the a mobile phone causes no interference to a planes systems. However at the end the pilot made a good point...
Every system which is used on an aircraft has been carefully tested to ensure that it doesn't cause problems with oher aircraft systems. For them to be confident that a phone causes no problems they would have to test each one available in any market (just incase someone flys internationally

)... Given the amount of testing that would be required it is easier to simply say "no phones in flight".
Of course this explaination doesn't cover other electronic equipment which may be used in flight (including phones in flight mode) as well as the mobile phone inflight trials which QF have been doing...