High Definition makes this game an instant classic
Graphics - mind blowingly epic, totally transformed the game, the amazing thing is the performance, despite the HD graphics (drools!) performance is high with everything maxed out.
i'm using W7 Professional X64, a Quadcore 3.0ghz with 4gb ram and an Nvidia GTX295 and getting 100fps, my friend with his midrange card (GTX260) is getting a steady 60fps, very smooth.
Sound: it's not bad, not much has changed.
Gameplay: run and kill hundreds of enemies on screen, lots of fun when played in short bursts of 30 minutes at a time, this isnt a game you want to play for hours.
conclusion?
this is a MUST BUY, it's highly recommended, prepare to pick your jaw from the floor.
Thanks for reading. :-D