Seven easy steps on how to make a "great" (relative concept) FPS "game" (also a relative concept) in 2010 and more importantly make a sh@t load of money in the process:

1) Obligatory post-apocalyptic setting - check

2) Sure recipe for success: 9/10 parts shooter with some superficial rpg elements sprinkled on top (so as to keep all the nerds satisfied) - check

3) Less than stellar (cute, sleepy zombie kittens really) single-player AI that gives the tacked on multiplayer a reason to exist and florish - check

4) Bad Russian accents ( thanks for raising the standards Bank of Nikolai actors) - check

5) Cool flying demon harpies - check

6) Plenty of Achievements for the xbox crowd - check, check

and finally

7) Trick "them" (meaning "gamers" *cough* talking wallets) into thinking that you are just like that other critically-acclaimed post-apocalyptic game that starts with "S" and was made in Eastern Europe in recent years, when actually you're not - Really big check

I'm not pointing any fingers here but *cough, cough* Metro 2033 springs to mind for some reason *cough*.