Well, I've not had a whole lot of time to play it but I must say, they did a very good job with the game despite all the nay sayers giving crap reviews of the game. It's exactly what I expected it to be for a Duke Nukem game. Macho content with explosions, bad movie one liners(tasteful ones), some meme references, and the list goes on and on. The games controls aren't complex and are almost reminiscent of Duke Nukem 3D. You can only carry 2 guns which isn't too bad since ammo doesn't seem to be too much of an issue. The few boss fights I've done have been creative and require you to take cover in some parts of the fights. I especially like the finishers you can do to them once you have finished off their health bars. But I don't want to give too much away.
I have yet to try the multiplayer stuff for the game but I must say, the single player experience fell is certainly fun. As for the poor reviews, I don't think they understand the whole Duke Nukem character so they don't get the whole macho approach the game has. I don't recommend the game for children under a certain age due to the level of sexual content the game has and references.