I responded to this thread back on page one and it's surprising how much my "must have" list has already changed:
Must Haves = Gears of War 2, Guitar Hero World Tour, Fable 2.
Off the list = SW Force Unleashed
The "on my radar" now includes:
Banjo Kazooie (might be a Xmas present, since it's only $40)
Fallout 3
Prince of Persia
Mortal Kombat vs. DC
Tomb Raider: Underworld