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The important caveat about that swarm is that they don't do their own mapping of the volume they're navigating. Instead they use several large and expensive cameras position around the room for navigation and tracking.
Instead, they give the drone vision problem to another research group:
http://www.youtube.com/watch?v=WoMrPKCpWXw
Note the title card, first author is the same but the second and third are different. It looks like their lidar test system is too large for their smaller quadrotors. So they do the sensible think and separate the two problems. Either way, when they bring it together they'll be more than capable.
Met one of the originators of this neat idea yesterday: http://matternet.net/
Basically a packet network for... packages, using quadrotors. Nearly feasible today, likely very doable in a few years. In EP this might be a convenient system for small scale transport around habitats and in roadless terrain on Mars and exoplanets.