Really dumbed down explanation: Teh Org is pretty much like the Federation (of Star Trek) for a whole bunch of World of Darkness LARP games across the US and parts of the world (Brazil & Israel for sure). There's garou, vampire (cam & sabbat), mage, changling, and prolly some others I forgot to mention. Players are allowed to travel between games because there's a set of By-laws that tie us all together; a lot of it is left to house rules though to give us the freedom to run things as we see fit. So really which you choose to attend depends on where you live and even then some are lucky enough to have multiple games within reach.
The typical summer/spring/outdoor weather location is in Warwick, RI but this past winter we were lucky enough to have use of Camelot in (oh god pulling a blank right now) south-eastern Mass? Anywho, because our playerbase is located in RI/MA we tend to hold game closer and letting our imaginations take the drive out to the Cape.