They greatly improved the graphics over the original. Alot of the gameplay is faster and more intense than the original game. The one reason I did not give this game a perfect 10 is because the online play is glitched at the moment. It is hard to get in a game or stay connected online. Hopefully this will be fixed soon with a patch. The realistic difficulty setting is very challenging. The now allow you to scan your face for your character with the PS3 eye. You definantly have to play in a tactical manner to survive, run and gun will get you killed. It's nice to see a more hardcore and realistic shooting game out there. I don't know what the big fuss about COD4 is. It doesn't even have a coop option. And there are no lame perks like the Martyrdom perk. Once they fix the online play this will definantly be my favorite video game to play online.
If you own Rainbow Six Vegas' first installment, pass on this one. Ubisoft has greatly improved the choppy online performance and sound glitches, but that's about it. They still have the same maps, save two or three, for online play. Do yourself a favor and get Call of Duty 4: Modern Warfare.
Compared to the first one this one is better. The new character customization is a nice addition. There are a few glitches throughout the game that are quickly overlooked by the fast pased game play. If you've never played Rainbow before your not missing anything. This is not a sequel but a continuation. The game play is pretty much the same as in the beginning. This Rainbow strays from the Vegas strip and spills into the back alleys. The environment is more industrial. If your looking for another COD4 this isn't it. If you want a solid first person shooter this is.