Chad Yakobson was just on the Brewing Network. He claimed to have a brew full of Butyric Acid and Brett ate it up and produced pleasant flavors. I think he said it took 6 months.
Interview starts sometime after the 50 minute mark - http://thebrewingnetwork.com/shows/866
Here is a synopsis of what Chad at Crooked Stave said at 1:51 in the show. Chad made a no boil beer which he spontaneously soured. The result has a lot of butyric acid (he didn't say anthing about vomit but indicated that people didn't like it). He then did a 100% Brett primary fermentation, blended it and aged it for 9 months.