rotating-GM has never seemed like a good idea to me. "oh sorry guys, i forgot it was my week, i don't got anything ready." ...or "ok, all that stuff last week was BS, so i'm erasing it. X,your character didn't die. Y you didn't die, but you still used the [amazingly rare 1shot item]. Z instead of getting all that awesome loot, you get [this] instead. and this dungeon sucks kinda, and i'm bored of it and wanna go another direction, so that was the boss and you're outside now. So you're back at the inn..." (this is probably exaggerating, and yet probably not completely made up either.) 1 campaign should be 1 gm. if you want multiple games, just join something else on another night. if you wanna play different campaigns each week, that's less bad, except then you end up waiting however many weeks extra between each game. which gets all the worse if you prefer one of the games significantly over the others. all that aside; "Dogs in the Vineyard" ? sounds like some pretty heavy religious & moral propaganda there, disguised as an RPG... that plus the way that the "betting" system for conflict resolution is described (at least in the wikipedia article) makes it sound like it would take the simplest conflict and drag it out for ages, if both sides get stubborn. tl;dr, neither of these sounds like a setup i'd want to play under, tho i won't try to predict what everyone else's reactions might be.
