"Good news, the game is incredibly successful beyond even my expectations," writes producer Gordon Van Dyke in a forum post. "We have reached server capacity, but the bad news about this now [means] some people can't join unless someone leaves."
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More servers are currently being added to resolve the issue, and in preparation for the PlayStation 3 launch of the $15 game tomorrow. A PC release is due in September.

2 shots to a tank's rear ends it, it seems.