While counter-intuitive at first for a pc player (who are used to right hand ovement, left hand action), I find that the controls are actually not bad at all. The mouse enables much more precise movements and since the camera is locked to only 1 plane of movement putting it on the mouse would be waste of an axis. Furthermore I think it's may actually be a balancing thing, since with the mouse controlling direction, the player is unable to dodge and shoot at the same time, thus rolling arround is less overpowered as it would have been otherwise.
Actually the only issue I have with controls is that there's too many keys in use all over the keyboard: e,q, enter, backspace, shift, 1,2,3, space,... Some of these could be eliminated or, as reason why I'm waiting for the patch - remapped.
In short - it takes a few minutes to get used to, but it's not that bad as people portray it to be.