Maximum PC has posted a giant interview with George Broussard, the designer of the actually released Duke Nukem games, and Gearbox's Brian Martel and Randy Pitchford. All of them had something interesting to say.
Broussard mentions how engine changes and customizing them was perhaps the biggest thing to hurt 3D Realms in trying to finish the Duke Nukem Forever project. The lawsuit battle with Take-Two, Broussard's relationship with Randy Pitchford and the way Gearbox was able to leverage their relationship with Take-Two all played a part in the game finally getting a release. He calls it: "the result of several back to back miracles that people will get to see this game. Imagine flipping a coin 5 times and getting heads each time."
Martel talks about how the EDF soldiers were toned down a bit from their sci-fi look, as they looked a bit like the "Halo guy" and Duke would look out of place next to them. He also says the weapons will be "really modern versions of everything you’d expect from a Duke game."
Pitchford mostly talks about how he missed the Duke as a character. One that has a lot of attitude and who can get away with doing ridiculous things to simply entertain us. That concept of pure entertainment is something he's very serious about. According to Pitchford, there are enough games that take themselves too seriously already, and Duke should be here to remedy that. Sounds good to me.