Looking from a personal standpoint here's my top holiday games (or games you should have at least bought some time in 2009 for releases of that year)
1) Modern Warfare 2 (As long as your willing to pay for Live. After putting in 25+ hours into the online mode I have quite the addiction)
2) Forza Motorsport 3
3) Left 4 Dead 2
4) Halo ODST
5) Shadow Complex
6) Secret of Monkey Island remake/graphics upgrade
7) Borderlands (Another multiplatform title but damn good)
8) Halo Wars
9) Magna Carta 2
10) GTA Liberty City Stories if you have any interest in GTA.
I would have said SFIV as a must have but with SSFIV due out in 3-4 months I would just wait for the re-tweaking and new characters as well as the extra online modes and hopefully lag free gameplay.
It's just that simple.
