All I confirm is that it'll be something we've never done before. Look for more information as we actually get closer to the Summer months.
Something you've never done before can still include an us Vs. them element with an ultimate winner though. The event in 2010 was "something you've never done before" and it really didn't foster the community. Heck, by the time we got the event people were tired of it pretty fast and it dragged on for far too long. The events in 2007, 2008, 2011, and 2012 all fostered the community spirit and gave us something to pull for. The one in 2009 with Camp Chaos, while it did have the us Vs. them element to it the community aspect was barely there was nothing to really work for as team with an ultimate winner.
Look at what's worked in the past and take that to heart. People want the summer event to have a team element to it because it fosters a good sense of community.
Or the demi-god christmas event (in fact, the event where overseer and sentinel build their ship on the event page is probably my favorite event ever)
Or any Easter (maybe not this one, since the eggs being in posts and the "switching" mechanic kinda kill any conversation in the even forum)
Or the pie-eating contest
Or the 2008 Rejected Olympics
In fact, even though both Olympics were about bite-sized flash games, the 08 event presented them so much better because they knew they were bite-sized flash games, and treated them as such. You never played one for more than 30 seconds, and the different assets for each made them feel fresh when you had to play a certain type more than once.
2012 on the other hand, took those same 5 flash games, go rid of the variety of assets and backgrounds, and extended them from bite-sized flash explosions into droning tedious finger killers.
They assumed that if people liked playing the games for 30 seconds they'll love them 10 times as much playing them for 5-6 minutes!
I may seem like I complain about everything, but there's a method to my madness.
So, something to do with fluffs and the end of this event...
Diedrich carries fluffs to every corner of Gaia, expecting to spread cuteness and cheer across our lovely nation/world/whatever. However, as there is no protection force in Gambino, Aekea or Durem, the fluffs quickly over populate and take over these towns. The event will make use of forums, the world map, towns 2 (I expect the full version will be out around then) and zOMG.