DRM and Locks
I've seen the argument that given that a competent hacker can strip the DRM from a file, that it's pointless. I wonder if these people also don't bother locking their house as a competant lock picker can open those locks in just a few moments.
The jury is out as to whether or not this will cause a jump, a slide, or make no difference to sales. What it will do is make it easier to locate this stuff posted on pirate sites because just like locks on house doors don't stop the skilled, DRM free means that the barrier to "sharing with all your mates on the Internet" is a lot lower.