Hi again to my fellow Carolina girl! The Disney PhotoPass CD can be a great value -- for one price you receive a CD with all the photos taken by Disney photographers on your vacation. Currently you can pre-purchase the Photo CD
here for $99, a savings of $50 over ordering one after your vacation. You could pre-order the CD for your December vacation now, and then view, edit, and order your photos on the CD when you return home. If you don't pre-purchase the CD before your trip, you always have the option of buying one when you return, but you won't be able to receive the lower pre-order price.
Now, with regard to your question as to whether you can
always pre-purchase the PhotoPass CD: unfortunately I can't guarantee that. The pre-order option disappeared for a while late last year, and was available only to certain people via links in emails. The current pre-purchase discount offer for everyone returned in April, and I hope it's here to stay, but with Disney, things are always subject to change. I'm budget-minded, so I can understand your not wanting to part with the $99 six months before your trip. However, if you know you definitely will want the CD and saving $50 is important to you, your safest best is to pre-order the CD while you can. I wish I could assure you that you'll be able to pre-order one right before your trip, but based on past history, there's a chance you may not, and I don't want you to miss out on the offer.
Thanks for visiting me again at the Moms Panel, Adrienne! Feel free to come back if I can be of more help to you! Have a magical vacation!