The photographers are all over the parks & at the events too. You can have them take as many pictures as you want. They give you a card when they first take a picture of you and they scan it every time a photographer adds pictures to your card number.
The beauty of it is that each person in your party can have one card & they can combine it onto one CD in the end. We always slpit up to maximize our park experience. I think PhotoPass have a max limit of pictures per CD like 400 or something. With our group of 11 people last year, we bought the CD and never reached the max photos per CD.
The CD was nice to have and easy to cost justify with so many people pitching in.
For a cheaper option, you can buy pictures al la carte(4x6, 5x7, 8x10 etc) too.
The pictures are very high quality & the photographers always seem to be in the perfect place at the right time.
Or just ask friendly people around you to use your camera- that works too!