Personally speaking I would not like the use of mobile phones on an aircraft. That said if the technology is now available to allow the use of mobile telephony in a safe manner then commercial pressure will ensure that most airlines will allow its use, especially those which rely on additional services to increase revenue (locos)
It is going to be intrusive though and some of the suggestions already put forward on this thread, such as banning the use of ring tones, is not going to work. One of the reasons you hear that annoying nokia ring tone all the time is, often, because the phones owner is too stupid to work out how to change it, the task of switching the phone over to silent mode while on a plane is beyond such people.
There will have to be limitations and restrictions though. For example, if I were on a night flight and was woken by one of the luddite's phones singing the Nokia song I would be extremely annoyed. The only way to stop this would be for the Captain to turn off the entire system.
Mobile phones have their use but in todays world they have become intrusive and for some people they appear to be surgically attached to their body. I had lunch with a colleague yesterday and I'm not exaggerating when I say she must have received and sent at least 30 text messages during the meal, god knows what she was chatting about. Anyway, I've crossed her off my lunch list....