I used to play with others on private worlds, and even on public servers, since at least 1.0.0 it just says it's loading and or connecting for an extremely long time. I decided maybe it would be fixed, so I waited and waited for it to be updated, but it hasn't yet. So I created a real to see if that would be a problem, and it was. It just says loading and loading and doesn't end.
http://i.imgur.com/ERsz7V9r.png