I've heard them called both around here, but I don't care as long as they're chocolate! Oh, and hot fudge and whipped cream would be nice, but no cherry on top - I'm on a diet!
Don't use either. I had never even heard the word "jimmies" until it was used in a Simpsons episode where Marge used them to temporarily blind some Ice Cream Shop employees
I thought of this thread this weekend. I was at the mall, walking by Brighams and saw a group of people eating icecream. One lady said, "Just the right amount of Jimmies".