[@Shoryu Magami]
Yes, that is entirely accurate, I will play in the game just like any other player. The rule about having the next poster decide was born from a wish to play a game like this, but not have to answer for the whole world. Instead everyone is a little bit of a GM and to be fair, if the whole group chips in and offers up their creativity it should be a far sight better than if just one guy was in charge of it all. 
I guess you could say that it is the story, the adventure, that is the main part of the game, which is a bit uncommon as many PbP-rps focus heavily on the characters. So I know it's something of a challenge for people, but that's what roleplaying is all about. For me at least.