> There don't seem to be any publicly available libraries focused on this kind of thing, so I assume that they develop their networking stuff mostly in-house.
Interesting. Enet seems pretty barebones, but I guess that would be beneficial for games where there can be a lot of variance in gameplay, what with the parent post's explanation of the level of precision required.
Have a look at RakNet (http://www.jenkinssoftware.com/) or enet (http://enet.bespin.org/).