Okay, let's say it shows there are 350 players online. It then shows I'm in Lobby 6.

What's the whole deal with this "Lobby 6" thing? Does this mean there are other players in other lobbies? Is the 350 just for Lobby 6 or is that the number of players online for all the lobbies?  What if myself and my friend log into the game? Is it possible we will be in separate lobbies and will not be able to see each other in the game?