It's a compass rose, thematic with the Map and Territory metaphor for rationality/truthseeking.
The real question is why does NATO have our logo.
Ah. Thanks! (by the way, when these questions get answered, should I take them down or leave them up for others?)
Why does LessWrong use that little compass thingy that serves as the North Atlantic Treaty Organization's logo? (except with four additional spikes added diagonally) Was it just a coincidence?