I got the orange box about two weeks ago. I'm surprised at how superior TF2 is to the other games in the box. I'm currently getting some mods for Portal, I hope they will sprinkle some life into the game after my 3 completions.
Anyone than hasn't completed Crysis on Delta difficulty should try it out. Much more fun! Boxing dead chickens is also a lot of fun (in Crysis, of course).