Graphics tablet users are an odd bunch. They’ll tell you how a mouse is a horrible input device. How you’ll eventually end up with a medical device wrapped around your wrist while they draw pretty pictures of flowers and mock up logos with a pen. That love of the tablet inevitably leads them to one company: Wacom. Frankly, there isn’t another tablet maker out there that even comes close--which puts the company in an odd position. How do you upgrade a product that’s already near perfect?