What did Pro do?
In my Nintendo Press Conference thread (and the NWR Live Blog, if I remember correctly), all throughout the Press Conference he was continually spamming (well, him and another user) nonsense posts, easily doubling the size of the thread and making it extremely difficult for anyone to follow. He was warned numerous times by mods and even Lindy, but just kept at it until they finally had to bring the hammer down.
Well, that's the reason he got a temporary ban this time. He's rather infamous around these forums for trolling.