Liked the event, but as a gamer I belive I am a little... inclined to compulsive collecting. Anyway, it was fun.
To search a bad side... short. Too short. Actually if it lasted 365-eplsilon days it would still be to short. Also, some of the hat seemed a little out of place - I mean, if the badge is called Necromancer, why a samurai hat? a bushido hat should go to the sportmanship badge, to the necromancer give a Skeletor mask... Also, I have the felling that some hats linked to vote/rep are harder to get by on lower traffic "board" (read: SharePoint overflow, 18 mortarboard badges from the start of times18 mortarboard badges from the start of times and so on..).
Suggestions for next time? site related hats. I really hoped for a Clippy hat on SPOverflow. Also - what about merging hats and badges? Leave badge as now, but add a flavor image like for hat. The whole with a rack page as a bonus, that shows the badges for all sites.