Emirates has become the first commercial airline allowing in-flight mobile calls, though it seems they are still in some trial phase.
See:
http://news.bbc.co.uk/1/hi/world/mid...st/7308041.stm
These will presumably be billed like a roaming call a bit like the services on ferrys and cruise ships. Many other airlines (Ryanair, Quantas) have also been promising services for ages, but Emirates has taken the first step.
Expensive public satellite phones have existed on long-haul flights for ages but these have been mainly pulled out due to tiny useage by passengers and not only because of their high rates. I can't really figure out if mobile in-flight calling will really be such a huge hit. Why can't they just concentrate on broadband and wifi instead?