Hello! So I went down to the apple store but didn't bring my whole computer so they couldn't diagnose it -- also priced out a new mouse (50 bucks to replace my wired, 60 for a wireless) and thought -- **** it, I'm gonna try again. So I went home and used a Q-tip in alcohol, rubbed it on the ball 5x clockwise, counterclockwise, right, left, up, down. Then I put it on a piece of clean paper and rolled the heck out of it. Now it works. I read on another site that it's the finger grease that reduces the friction of the ball and that's the problem. The clean paper pulls the grease off and helps rough up the ball again. Remember when the mouse is new the roller ball is strangely / intentionally rough.
So that's my experience! Success. Thanks much everyone for your help. If at first you don't succeed....
