WASD is natural for a FPS gamer like me - I'm so used to it that being forced to use the arrow keys for anything other then typing documents is just weird - really, it's a little odd, but I just can't play games with the arrow keys, they're too awkward for me.
However, I can understand that WASD can be uncomfortable to people who haven't used it before and let me tell you - using those keys is like most good things in life. An acquired taste.