Jerry Holkins, a/k/a Tycho Brahe of Penny Arcade, announced that the first free DLC for the duo's game, On the Rainslick Precipice of Darkness 3, is nearly complete and will be available soon. He hinted that it would arrive around PAX Prime in September, but there's always the possibilities for delays. The DLC is called "The Lair of the Seamstress," which is only a name the guys at Penny Arcade could possibly get away with.
Tycho also announced that developer Zeboyd is working on both another free DLC AND the fourth chapter in the series.