When will airlines face the facts that this stuff about mobile phones interfering with aircraft navigation systems is a load of old toot?
Think about it. On the average flight there is almost certainly someone who forgets to switch off their phone or Blackberry. On the average flight in China that number almost certainly increases as the number of people who follow the announced instructions is distinctly lower than elsewhere.
So, if we assume that every commercial flight that has, say, one active mobile phone on it and there are, let's guess, 100,000 flights per day worldwide (extrapolating from this article that says there are about 29,000 flights per day in the USA alone), and that we'll just focus on the time period since 2000 as mobile phones were commonplace and Blackberry's coming into regular usage. That would mean that 7*365*100,000 or 292,000,000 commercial flights.
To my knowledge, there have been no crashes attributed to mobile phone usage and 0 out of 292,000,000 would seem to imply a fairly low risk. Other opinions seem to be divided (here, here and here).
So, it looks like phones are pretty safe and they have transmitters built into them. This would seem to me to indicate that the insistence on making me stop using my iPod 20 minutes before we land (I've wiped it and resynced it so I have more music now) would seem to be completely unnecessary.