I had just purchased the premium AP with the DVC rate a couple weeks ago. And I had heard the rumors of the discount reduction, so I made sure I bought everything I wanted before the discount went down.
The funny thing is, I knew in October that there were things I wanted to buy, but I deliberately waited until December to get the better discount than the 10% standard AP discount.
I think I might need to write to the WDW Guest Relations email to inform them that I spent more on souvenirs in December than my three previous trips after purchasing my Premium AP than I had with the standard AP, solely for the better discount rate. I will let them know that I will return to my usual lackluster spending now that my discount went back to what I'm used to seeing. It probably won't do much, but Disney should be aware of the impact the discount perk had. I'd rather give up the DisneyQuest admission than the shopping discount.