Christ, there's some miserable old farts on here, especially considering it's a tech site. If there's some class of consumer device that brings down planes, it hasn't managed it yet, and if it exists, then leave that class of device banned. Other than that, why assume that "electronic device" refers to "something that will annoy your whingeing arse"?
Everything is electronic these days. I've been harassed before for an eBook reader. It barely uses any power to begin with, but no, can't read for large sections of the flight. That would be dangerous...somehow....somewhere....in some alternate dimension...
If I want to fire up my PSP on a flight, how is that any different to you watching the in-flight movie? And if my PSP or reader is going to bring down the plane, why wouldn't your wristwatch or the headset monitor? I wouldn't be surprised if my own body put out a larger EM field than some of the electronic kit I use.
The fear over EM fields here is exactly the same as the fear over wireless routers in schools; a load of crap perpetuated by people who don't get how stuff works. As for "keep them banned, I'm grumpy", no thanks. You can stare at the back of the seat in front for 10 hours if you like. I'm going to play God of War.