But no. The Call of Duty: Black Ops commercial didn’t show a frame of the game, but some people bought it anyway after they saw Kobe Bryant wielding an assault rifle and Jimmy Kimmel firing a rocket launcher. Halo 3′s marketing campaign involved (to name a few) an 8-minute live-action film, a wicked diorama, and a limited time-only Mountain Dew flavor, but you had to go digging if you wanted to know what the game actually looked like before it was released. Then there are the CGI videos that are intended to emulate the feel of playing the game; those always look good, but they rarely convey what it’s like to play the game.

Portal 2 joins the ranks of the second batch. It doesn’t show us the game in action, but hey, at least this one shows how the Portal gun works. That’s more than I can say for most.