From what Harry and Ron told me, Divination under "Professor" Firenze was very different from Trelawney. Had we had him for that class from the beginning, I might have stuck with it longer. Even so, though, I'm happy I dropped it. I admit my mind wasn't on Arithmancy, though---I was busy analyzing the situation, since I knew that things had to be coming to a head between Umbridge and Dumbledore.