We just came back on July 19th. Photopass is fantastic. The photos are only available online for 30 days from the date that the first picture was taken. We purchased one of the photos at MK before we left, it is great, we were posed in front of the castle and they added a border to the photo that has Mickey and Minnie as well as "The Happiest Celebration" across the top. In other pictures they added Tinkerbell into my daughters hand. An 8x10 cost me $18 incl. tax.
They also have photopass at the water parks, but you must buy the photos at the park, they are NOT available online. These photos are less expensive. They give you a bracelet every time they take your picture.
Take advantage of photopass, you are not obligated to buy any of the photos. So, use it every time it's available. You might end up with a fabulous momento of the trip. We did.