Before I chose between Magic Mouse and Trackpad, or both, I asked quite a few friends who have used Mac for long time. Surprisingly, all of them don't like Magic Mouse, and told me that any decent non-Apple USB mouse is better it. They do recommend Trackpad (since this is a mini, with no built-in trackpad) for multitouch and gestures.
So now I am using the Trackpad and a Logitech USB mouse, and very happy.
I think Trackpad would not be good for tasks like drawing.