GTA4 was a major letdown for me, as were Mercs 2, Saints Row 2, and Mirror's Edge, so all are off my list. Left 4 Dead failed to impress at all, and TF2 was no match for CoD4. Top of my list, hands down, Fallout 3. I spent over 80 hours with the game so far, and I could easily see myself going back a few save points and…