Gears of War 2 is just simply BEAUTIFUL. Anyone who says otherwise has either never played the game, is blind, or trying to hate on the 360. One of the things I find the most beautiful is the waterfalls. On an HDTV, it's hard to believe those are in-game graphics and not a real life movie.. nothing compares to it IMHO. At least not until Alan Wake/Heavy Rain, and even still, it's going to take ALOT to impress me after this.
Little things also, like if you shoot into the water it's so realistic it's crazy. Even the way the water ripples afterwards. Try throwing a 'nade in the water. Or shooting various different weapons, all have different effects.
Proud Owner of: 
250gig FFXIII SE Xbox 360, 250gig Xbox 360 S, black Wii, 120gig PS3 Slim, soon to be 3DS *___*
