By this stage, Facebook's plan to bring internet to the whole world with a fleet of drones and lasers is pretty well documented: what's a little vague has been the details — until now.
Speaking at the Social Good Summit in New York, Yael Maguire, the engineering director at Facebook Connectivity Lab, spilled a few details. The 'unmanned planes' (Facebook seems to be steering clear of the term 'drone', given what US-made drones are normally associated with doing over foreign soil) will be about the size of a 747, but far lighter, and solar-powered. In theory, that combination of huge wingspan (and, presumably, quite a few solar panels on top) will let the 'planes' fly more or less indefinitely, at high altitudes - 60,000 feet or more, in order to stay above the weather, and other aircraft.
In terms of timescale, Maguire wants a prototype aircraft flying sometime in 2015, with actual internet-beaming-goodness following in 3-5 years' time. As for who will actually deploy these things? That's still to be determined, in typical Silicon Valley solution: build the technology, and the market will create itself. [Mashable]