If you're playing a net game, and you start to see flashing red arrows in the upper right - these are an indication that the network link between you and your opponent is disintegrating. There have been instances during beta testing where we've seen these arrows with no real effect on the game or play, but usually they lead to a "your opponent has disconnected" message.
I've no real technical infomation on how pop-pop plays through lag, hopefully one of the andrews can chime in here with information, or one of my fellow beta testers.
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