The fabric is Joel Dewberry, and though you can't see too well in the pictures, I used lime green thread in all the topstitching accents, and a coordinating print for the inside lining.
I am really pleased with the outcome. The pattern was super easy to follow, and the hardest part was cutting and pinning through all the layers of canvas that are sandwiched between the exterior and lining of the hat to give it its shape. But the heft of the hat is wonderful, and the fit is perfect. I had Lyndsay close her eyes while I put it on her head just to make sure. This will be a great accessory for reading (and friendship bracelet making) on the beach. And will go perfectly with the pink sunglasses I know she just ordered for herself. Tee hee.