GamePolitics reports on plans for an unannounced game in the Duke Nukem series "being developed in parallel by a separate well-known game developer under contract with Take-Two," after digging through court documents (Adobe Acrobat format) from a countersuit Take Two's Lawsuit against 3D Realms over Duke Nukem Forever. Their subsequent story on the topic adds further detail, as digging deeper reveals the title of this game to be Duke Begins, and the developer as 2K Games, but the statement by Apogee/3D Realms makes it sound like this project may have already been cancelled:

On October 22, 2007, Apogee, Take-Two, and 2K Games entered into an agreement in which Apogee granted 2K Games the exclusive right to develop and publish a new videogame based upon Apogee's Duke Nukem franchise... The new game was given the working title of "Duke Begins" and is not the same game as the DNF game...

The original development schedule for the Duke Begins game provided that the game was to be completed and commercially released by mid-2010...

Take Two and/or its subsidiary 2K Games halted or otherwise cancelled all development work by the third-party game developer on the Duke Begins game in April 2009... without Apogee's approval or consent...

When Apogee confronted Take-Two and 2K Games about the... cancellation of the Duke Begins development work... Take-Two and 2K Games simply denied it... Take-Two and 2K Games are taking such actions with a goal of pressuring Apogee to sell the Duke Nukem franchise rights to Take-Two for less than their true value.