Played through the demo. First bit is just a (massive) graphical update to the last boss of Duke3D in the stadium (sorry, no goodies in the blimp) which appears to be the opening of the game. The second sequence is some time later out in the desert areas we've been seeing since those screenshots in '98, where you fight a bunch of pigs with a variety of weapons, including the new shrink gun and a rail gun that seems to fulfill the sniper mode, as well as some classics like the ripper machine gun, the shotgun, and the RPG. There's also a brief driving sequence which is neither here nor there. You go into a mine by breaking some planks, and Duke quips "A crowbar sure would be handy about now", so references to "peers" are still in there, and I chuckled at that one.
I think I will eventually play this. The gameplay is solid, because Gearbox, and the weapons are all there, whacked out and fun as ever. Duke is crude, and sophomoric, and everything else people said it would be, but it's also fun. My only real complaint is that the jump is pretty crappy, but the controls list a button for the Jetpack (J if you were worried they'd changed it), so there's that to look forward to.