I have to chime in and say that I think the mouse acceleration problem is a very serious issue.
When I first played the demo I felt it pretty bad but after lowering the graphics settings it seemed that most of it had gone away.
Unfortunately when I am trying to play the retail game I have terrible "mouse lag" despite turning the settings down a bit like I had done in the demo.
For me this is a deal breaker and unfortunately it means that I cant really play the game until it is either fixed completely or the performance is improved sufficiently so that the problem becomes less noticeable.
Also, that this would be a feature to simulate weapon weight is preposterous. Moving a medium sized weapon is a fast process, what takes time is stabilizing the aim after movement. This would be better simulated by increasing the size of the firing cone after movement.
