Which game should I get? - Brink, Duke Nukem: Forever or Portal 2?

I have to say that it's between Duke Nukem: Forever and Portal 2. For me, I'd say that Portal 2 looks really interesting; the first game was very interesting and involved a lot of puzzles (and some humor), and I can't wait for the sequel. However, Duke Nukem has been waiting years for a sequel or a remake, and I think it'll be pretty good. Either way, you'll still be getting a great game.