If you ignore all the side missions, Truth clusters and training your assassin recruits, probably about 15 hours. However, I'm about to hit the 40 hour mark even though I beat the game not to long ago.
#3FlatPennyPosted 2/25/2012 6:25:22 PM
Doing everything systematically, all them took me about 30 hours to do everything. (not counting multiplayer trophies) --- Currently playing - Resident Evil 5 (Ps3), Zone of the Enders: The 2nd Runner (Ps2)
#4lostfan132Posted 2/28/2012 5:00:05 PM
straight through the story about 10 to 12 hours, with everything 30+