Finally: I've been asking the question for several years: when will media servers on planes be used to provide in-flight entertainment over Wi-Fi? The answer is now . Aircell told me years ago that they had provisioned the ability to put media servers on planes, and were waiting for pieces to fall into place. Its public trial with American Airlines on a couple of 767-200s will start this summer. It's a logical connection that when you have people on a local, high-speed wireless network that you could deliver content to them for free and for a fee. Given that the majority (sometimes entirety) of people on a flight have some kind of device with a screen, why build in miles of wire and clunky seatback entertainment systems? One of the best, Virgin American's Red, is still slow, hard to navigate, and of poor quality relative to even the worst tablet or netbook. Alaska Airlines never installed such systems for reasons of cost, and rents its digEplayer instead—a portable tablet preloaded and precharged.…