The Balloonist is The Believer
It has been pointed out that McSweeney's is selling subscriptions to a new monthly publication called The Believer that's co-edited by Heidi Julavits, which perhaps means that The Balloonist was never The Balloonist, but The Believer.
The Believer: 12 issue subscription [McSweeney's store via The White Shoe Irregular]