Actually, you can even argue that the blockchain itself is a similar concept. It's a Schelling-point-based system for determining consensus, except its scope is limited to the simple question of which transactions came first.
Right - I guess the open question at this point is how much weight those mechanisms can bear. Bitcoin has a very easy version of the problem, because all they need to do is time-stamping, where you just have to follow the rules and run your software without hacking it to stay in line with the consensus.
As described the problem TruthCoin is trying to solve puts a lot more stress on the consensus mechanism, because it requires the participants to do more work to stay in line with the consensus.
In practice I think what ends up happening is that somebody publishes a feed and everybody pulls their results from that and "votes" as they're told to by the feed. This may not be too bad in itself as the feed is probably not too bad, and the people publishing it probably have an incentive to keep publishing good data. But I do worry that this system will make it hard to get off the de-facto default data feed if it starts producing bad data, since it's designed to punish people who step outside the consensus...
