Dead Rising 3 has made it PC with a full-on Apocalypse Edition, digital only. This provides an opportunity to wacky zombie-bashing both in solo and co-op modes. The amount of zombies on the screen at any one time is quite impressive.
Info via wikipedia:
Following in the footsteps of previous installments, players control new protagonist Nick Ramos in third person. They will start by searching for supplies and weapons in order to fight many undead and complete missions. Dead Rising 3 is set in a vast, open world environment which is much larger than the worlds of Dead Rising and Dead Rising 2 combined. According to developers, the game can render three times as many zombies on-screen at once as its predecessor. Players will also be allowed to save their progress anywhere, as opposed to limiting saves to toilets. The game will include a “Nightmare Mode” for those who would prefer the traditional time limit and save options. The game will not have load times.