A board built for two
The term "Arena" does connote gladiatorial combat, and I was using the term jokingly in the case of Nicholas and Alexander. An "Arena" would be the site of a formal event that would probably be publicized like a boxing match: "Malin vs. Hoagland", that sort of hype, with "versus" the operative term. But a board for two or a handful of people to work together quietly does make a whole lot of sense to me. See my observations above on "collaboration systems".
--Robert