The beginning seems to go by quickly, but the later chapters seem to take longer (for me at least, also playing on Zealot for the first time). I'm on Chapter 13 with 8 hours in, so I'd say it takes a good 10-12 hours to beat the game, depending on if you get stuck or not.
I've heard anywhere between 8-15 hours, first time through.
There's 15 chapters, so you still have a ways to go. Especially on zealot.
-Just take your time and enjoy it. This game is awesome. --- Worst squadmate ever? ...Kanye West. In the middle of a shoot out he'll snatch your gun outa' your hand to tell you how his gun is the greatest of all time!
8-10hours seems to be the norm. I finished in 9hour on Hard(survivalist) my first run. --- My PC screen shots-http://s402.photobucket.com/albums/pp109/Darkspiret/ Currently playing: Team Fortress 2 - Killing Floor - Demons Souls
Fairly short. I'm sure it only seemed that way due to the lack of having to go to tram station to tram station. Also because going from chapter to chapter doesn't require the need for it. But the game is fairly short. --- PSN = AKA_Neku /// Too many games to play. I need to actually finish some of the ones I bought at full price.