Wow. Legendary? You know, it's the guys who made Turning Point: Fall of Liberty. So far, it has only achieved bad reviews.
Far cry 2 was kinda disappointing. Yes, the graphics might be good, and the use of fire is nice, but overall it's not that good. Firefights get boring, all the traveling is a pain in the ass, and the story is bad.
Saints row 2 was better than I expected. By the look of some videos, it looked very identical to GTAIV, just worse, but playing it was very different. It's cool, immature, and just plain fun, although it has some minor flaws.
Fallout 3 is awesome. It was one of my highly anticipated games of the year, and it succeded in being epic. Everything is just awesome. I'm not into multiplayer, so I really don't care if there is MP or not.
Gears of War 2: I haven't played it yet, due to not having a 360, but it seems cool. However, I would really only recommend it to people whom are into multiplayer, cause I heard the single-player experience is pretty short.
Mirrors Edge is actually the most original game here, as you can tell by seeing, it is not a sequel as all the other games. From playing the demo, I say this game is a must buy. It's just awesome! The gameplay is nice, the graphics are good, but the best is really that you can be good at the game, you can be excellent or you can just be a pro. When you've spend some time with the game, you'll see the opportunities in the platforming, and choose better ways to keep momentum and speed. Awesome game. However, there's no multi-player, only time-trials, but I guess you'll have a good time with those as well.
As for Fable 2, I don't really know. I liked the first one, but it wasn't mind-blowing. This sequel seemed good, but it was over way too fast, considering it being an RPG. Lack of multiplayer may be a minus in your eyes, (As I said above, I'm not into MP, so I don't care,) but overall a great game, it was just over way too fast.