Preheat oven to 400 degrees. Brush both sides of the bread slices with the olive oil. Season the top side with salt , black pepper, and rosemary. Bake in the oven until light golden and moderately crisp.
Prepare the topping by tossing together in a bowl the cherries, vinegar, and sugar. Let marinate for 5 minutes. Reserve.
Spread each bread slice with some of the goat cheese. Divide the arugula over the cheese and garnish with an equal amount of the cherry mixture. Serves four.