At SeaWorld, each time you get your photo taken, you are given a little card.
At Aquatica, its the same system, but you get a wrist band.
As long as you don't exceed a 7 day period, you can collect all your SW photo cards and Aquatica photo bracelets, and get a CD made of all the pictures for about $40 ($40 is their base price, apparently it goes up if you have a lot of photos). This is done at the adventure photo desk just inside the SW gates.
We purchased the CD on our Christmas trip, and ended up getting about 35 pictures in total, including snowglobe photos and Polar Express photos.
There were a couple of photo lcoations that couldn't be included on the CD. The photos taken at the SkyTower is one example. But the adventure photo rep said we could take the CD, once burned and paid for, back to the SkyTower photo kiosk and they could add those pics to the CD for another $10. We didn't bother, as we had the photos we really wanted, but apparently it was doable.
I don't know about Busch Gardens, unfortunately, and whether or not you can include them on the SW/AQ CD. That's one park that's still on my to-do list!