One big problem I always had with Macs is that a window is never in full screen mode. Sure, there's a guy up there in the upper right corner that claims to make the window full screen but in reality it doesn't quite do it. The result is that I can be going to slide the vertical scroll bar to get the window to go up or down and I miss by just the least little bit and click on the window behind the one I'm working with and suddenly there's a whole new window that I don't really want. It's annoying at best.