Wirelessly posted (Mozilla/5.0 (BlackBerry; U; BlackBerry 9780; en-US) AppleWebKit/534.1+ (KHTML, like Gecko) Version/6.0.0.285 Mobile Safari/534.1+)

The problem generally isn't flight safety but that cell phones in the air really screw with ground based cell towers. Since you are so high up your cell phone can 'see' a number of different towers and apparently they switch towers very quickly (because of your height and speed). I believe in the states the rule is governed by the FCC rather than the FAA.

It's the reason that the pico cells being added to planes to allow for in air texting/calling is okay. While your phone is on it locks onto the 'cell tower' on the plane rather than a ground station.