4. Gears of War (2006)
Remember the first HD "next-gen" game you saw? It looked like shit, didn't it? Blurry textures, jaggy characters--and it was all covered with a hyper-shiny coating that made everything look like it was covered in saran wrap. It was HD, and it looked better than the stuff you played on the PS2, but it wasn't really all that pretty. If it even had online play, it was likely just some shlocky deathmatch you could've experienced on PC. But then Gears of War came out, with its remarkable graphics, compelling story, and thrilling cooperative cover based shooting, and you were like, "holy hell, next-gen."
Gears was the first really next-gen-looking game. Bulky, meaty characters galumphing through realistic environments was what we all signed up for when we bought an Xbox 360, and Gears delivered. Yes, it was as grey and brown as they come (a problem fixed in Gears 2, when everything in the world shat rainbows just to prove that the Unreal Engine could render more than four colors), but it looked GREAT no matter the color. It was one of the first big 7th-gen franchises, and it showed what the hardware you paid for could really do.