If asked what i'd like to play most, I'd have to say "A really good werewolf game," followed by "a really good changeling game" and a "really good Mage game."
As to what I'd enjoy *running*, I'm really jazzed by Changeling: The Lost, but it looks so limited, particularly compared to the previous settings. The game is gorgeous, its concepts are rich--but it's SOOO Charles de Lint, "Evil Fairies Raid an Art Commune in Toronto, Film at 11." You can expand it a bit, but the characters tend to be made to be paranoid and isolationist. Old School Changeling was kind of dippy, at least in the way it tended to be played--The Eternal Revel (with a bit of monty python) rather than "My last meal shall be the mead of the gods and chocolates filled with passion before you condemn me to death by exile in the real world, la sir." But it had a strong quest structure, court intrigue, and none of that isolated terror feeling. The "things outside the fire" is all well and good for writing a short story, but I'm not sure it sustains a campaign.
Then again, is a campaign strictly necessary?
You could EASILY run Labyrinth in Changeling: The Lost. Totally. It's probably listed in the bibliography. But Labyrinth is a bounded story.
I don't want to run Mage. It's crazy-making.
Werewolf and Vampire seem the best suited for long-term, open-ended campaigns, and to be fair, I know Werewolf really well. After years of larping, I've actually run werewolf moots and other rituals. But I want to *play* werewolf, not run it!
Ach, the curse of the DM, we are doomed to run the worlds we want to live :(