CD Projekt Red has confirmed that they're working on quite a few different projects, with some not planned for release until 2014/2015.
The publisher told Eurogamer that they're working on two "A" quality titles planned for 2012. This will then be followed up by an "AA" quality game in 2013, with two "AAA+" games planned for release in 2014/2015.
The polish publisher also confirmed that one of the "AAA+" titles would be a new IP, meaning the other isn't. This suggests that The Witcher 3 is in development.