Unless that purchase happens *at* WDW or in the Orlando airport... (i.e. if you buy them on October 1, but for some reason don't use them to enter a park until October 4, they'll still expire October 1 of the following year)
-Rob
Yes, be sure to check the date, check the date, check the date.
We almost had that problem w/our APs that we just got a couple weeks ago. I got exchange vouchers from AAA in july, and we came to WDW the day before DD bday in Aug. We purposely did not plan to use the AP until DD bday so that we can come back next year and use it on her bday again (last day the AP will be good).... well, I exchanged the vouchers on the day we arrived so that we could check into our hotel on the AP rate, and got them back w/the expiration date being one year from that day, instead of the next day (DD bday). I had to go through several hoops to get that corrected, so the moral of this story is, if you get your APs before the date you plan to first use them, let them know to post date them so you get your max. days.
I have seen several posts saying that they expire one year from 1st use, but when I looked at the APs and it said plainly on them "Expires 8/1/2010", when I needed to use them on 8/2/2010, I wasn't taking any chances.
Also, another "perk" --- AAA Auto Club South (Florida, Georgia, and SC?) gives a discount on the AP, so if you are a member of AAA anywhere in the US, you can get that savings (about $30 per AP, if I remember correctly). You can do this at any Auto club south location (we went to one in GA.).