Yes ball swings for fast bowlers but it swings randomly.As I was playing 10 over match against India as a Pakistan and India really whacked Sami for first 4 bowls and then he created a beauty and this was big in swing which started from off stump and passed from his leg stump.Besides,couple of times I was able to produce the swinging yorkers which totally destroyed cpu and he was plumb LBW.However,the most fascinating delivery which I witnessed was from Umar Gul who who was bowling from off side and and bowl was ptched at middle and leg and swing into such extent that it hit it,s off stump.I will try to post some screen shots of it.