Independent developer Number None's follow up to Braid, the time-shifting puzzle adventure game, will be The Witness, an exploration-puzzle game on an uninhabited island. Hold onto that knowledge, for it will be a long wait before you get The Witness.
The developer recently began hiring for The Witness, described in job listings as "philosophical and quiet" and placing "a heavy emphasis on the way things look." That look will take sometime to nail down, apparently, as the game is slated for a release in "late 2011." That's a "hopefully" late 2011, according to the game's official, currently minimal web site.
Like Braid, The Witness is planned for release on multiple platforms, "whatever makes sense in late 2011," according to the official description.