That would be the largest video game leak since what, Half Life 2 ? Was there any real AAA source code leak in the meantime ?
There was also a leak of one of Ubisoft's games, not sure about source code.
Other than that notin gaming i don't think
And the HL2 gave us a nice delay. So everybody cheering for leaks I hope they are also cool about waiting longer for the finished game.
He posted many screenshots proving he has something authentic, tho.