Bastion developer Supergiant Games' next project is Transistor, a sci-fi action RPG slated to launch sometime in 2014. In the blog post announcing the game, Supergiant's Greg Kasavin says the developer hasn't decided on any one specific platform or platforms for Transistor yet.
Supergiant Games' freshman adventure Bastion launched in 2011, winning numerous awards and establishing itself as one of the best games of the year. Bastion has sold over 1.7 million copies to date.
Update: Logan Cunningham, the voice of Rucks in Bastion, has confirmed on Twitter that he's working on Transistor "in a vocal capacity."