Many airlines make it a policy to force passengers to turn their phones “completely off”. This is in complete awareness of “flight mode” features of phones. They really just don’t want to have to train their flight attendants to know how to verify flight mode on a multitude of devices or take the time to do it, even though there are always phones left on accidentally on almost every flight. It’s also easy to intentionally leave your phone on, simply by stowing it… even if it’s out, as long as the screen is off the flight attendants won’t care. If you have a laptop with built-in HSPDA/CDMA (very common now), flight attendants also won’t care (whether you’re using the wireless or not).

It simply comes down to form factor… small devices are all starting to look like and absorb features of cell phones and vice-versa. If you want to use one of these on a plane (with the wireless features turned off), then you’re at the mercy of ignorant flight crews and their airlines’ lazy, paranoid, conservative policies. If you want to use your laptop (even nefariously with HSPDA on), nobody will care. Of course laptops and cell phones are blurring their boundaries (with big rich-featured PDA phones that look like mini-laptops, and UMPCs), flight crews will find it impossible to tell who is violating the antique FAA rules (which are already way behind if you look at the list of banned devices – which include things that only receive signal and can’t possibly cause direct radio interference).

We are heading [slowly] toward one of the two scenarios:
1. an all-out ban on electronics that aren’t provided by the airline (built into the seats or portable units for rent)
2. an all-out un-ban of everything (once they retire all the old planes that aren’t shielded against in-cabin radio interference)

Because it’s impossible to bucketize all the new converged gadgets into banned and non-banned categories, they will have to ban or un-ban everything at once.