So I played through and beat all of Duke Nukem Forever...and thankfully I ignored the Duke-bashing 'cause this was a pretty fun game. If you're a critic and you're sitting down to analyze this game, there's tons of flaws to point out. The graphics appear to be first-gen Xbox (I imagine the engine is the same as it was for Prey), there's a very small variety of weapons (can't be more than 12 or so total, and that includes explosives and turrets), and the storyline is pretty minimal and basic. The game really does feel like a relic from the 90s, which is really the core of it's "problems". I put that in quotes because I really don't see it as big a problem as the detractors seem to.
There's something to be said for a game that's just "fun" and Duke is really tons of fun. What this game does really well is level design and scripting (ie. where and how you fight your battles; there are puzzles in this game, it's not just 100% shooting), including the bosses which I enjoyed, the balancing in the weapons (all of them are useful, it's a matter of taste), and the personality of Duke and his world. But you really have to like the extremely over-the-top machismo of the main character and the fact that he's pretty much a demigod in his world because of it (his "shield" is called Ego for cryin' out loud). If you don't find that entertaining and even comical, don't play the game 'cause for the entire 12 or so hours you're playing it (on Hard), you're gonna get it thrown at you much more than you think. Watch the videos, they give you a decent glimpse of what's to come.
That being said, I personally rate this game around a 7 or 7.5 with my personal bias bring it up to an 8 experience for me. I think it would be a fine $30 buy for most people (it's already down to $40 up here, so that should be very soon). But you really, really have to enjoy a very old-school feeling shooter that's all about personality, level design, and just plain fun with 5 year-old graphics, little storyline, and few weapons. If you can't enjoy that, don't play it. But if you can, this game can be just pure, unadulterated fun. I'm personally OK with a game with flaws and is about just tons of fun, but I can see why it gets bashed.
I was there on that fateful day, were you?