how many test chambers are there on portal 2?

Answer 1

Apparently there are 22 chambers/levels with many other plot sections and areas. the developers promised atleast 10 hours of gameplay.

 

Plus, there's the Co-op levels.

Answer 2

According to what I have read, 22. But around 10 hours of gameplay.

game just launched so no one has gotten that far yet.

Answer 3

the in game signs say chamber x out of 22. and that's not counting the co-op levels.

Answer 4

Probably 22 as I read. But I don't know if there's 'behind-scene' story.

Answer 5

There's 22 SP chambers and around 30 co-op levels.

Answer 6

There are 22 test chambers in single player, and 11 test chambers in coop.