Just beat it on Hard. About to start a New Game+.
My impressions:
The combat is essentially the same as before, except if feels slightly sped up, but overall it's better. My one annoyance is with the move when you vault off of someone, it goes into a double fisted slam when you land on a different opponent instead of letting you choose to attack a different character.
The story is the best it's ever been in the series, and ties in nicely to Arkham Asylum.
The boss fights are pretty good. Easily the best in the series, and you can see that they really took the Freis fight from Arkham City as inspiration.
The graphics, my goodness, on PC, with PhysX and Tessellation maxed out, it looks incredible. The snow is awesome, especially when you kick a criminal 15 feet and they slide through it, it just looks great. And holy shit at the (minor gadget related spoiler)
with PhysX, they have the mist-like haze that follows Bat's movement, you can see the particles cyclone around his body and fists, it looks amazing.
The game runs really really well on PC, DX11 never ran this well on Day 1 in Arkham City, and I can appreciate the effort that Nvidia and WB put into the PC port.
The City is much much bigger, and even when returning to the old portion from Arkham City, it really feels like a new city, I mean the layout will be slightly familiar but it's not the same at all, I had AC's map memorized and I still became turned around when revisiting the same areas in Origins.
This is easily the best game in the series, and if you hadn't told me, I would have thought it was Rocksteady making it. People shouldn't be down on the fact that it's not the same devs, as you can tell that these Devs really loved the source material and looked at it with respect.
Seriously, it's a great game, and if your a fan of either two previous games you should play this, preferably on PC if possible, but you should play this game.