Much of aircraft coordination with other aircraft, with airfields, with information sourcing to weather etc. and even to actual internal aircraft control is involved with secure radio contact that must not be disrupted for reasons of safety. Passengers mostly do not realize the incipient dangers always present in air transport even when general conditions are not threatening. To sacrifice any of this safety for convenience or entertainment of passengers is not particularly wise. To some extent much data for work or entertainment can be installed in hard drives before the trip and manipulated by computers during the trip without external connection.

Initially, slower internet was first availible in Europe from satellites at about 2002, but now broad band is availible.

http://www.nowpublic.com/technology/internet-airplanes-surf-and-fly-same-time

Question is, now how does an airline make money off of this.

Sand, I've worked in avionics and am a pilot and I'm pretty certain that the risks you speak of are minimal.

deffinatly a safty issue--the Boeing Dreamliner offers internet access and has discovered a problem with hackers, intenet access on planes is an easy terrorist target. I do beleive they are going to try to correct the problem rather then discontinueing the option of using the internet while flying--we'll see how that works out.

Interference depends on frequencies used, encryption,etc. I suspect it is doable. Would probably cost extra.