. Preheat oven to 350. Discard ends of bread loaf and thinly slice on a slight diagonal. Brush each side lightly with olive oil and place in even layer on baking sheets. Bake until lightly golden, 10-15 minutes. These can be made up to 2 days ahead of time, store at room temp in an airtight container until ready to assemble.
2. Let bleu cheese and cream cheese come to room temperature. Combine cheese, 1 TB olive oil, and white wine vinegar in food processor. Process until smooth. Can be made up to 3 days ahead of time. Store in an airtight container in refrigerator until ready to assemble. (I used a ziploc bag and then just snipped a corner off to squeeze it out onto the toasts when I was assembling the crostini.)
3. Preheat oven to 400. Wash and pat grapes dry. Remove from stems and toss with 2 TB olive oil. Spread sprigs of thyme out over a large baking sheet. Spread grapes over thyme and drizzle with honey. Bake until grapes are just beginning to burst, about 10-15 minutes.
4. To assemble: bring cheese spread to room temp. While grapes are roasting, spread cheese mixture over prepared crostini. Remove grapes from oven and top each crostini with a few grapes. Serve at room temperature.