Yeah, RiPPn and Kain's idea that Sony doesn't want consumers to buy games on sale is pretty hilarious.
It makes perfect sense. Sony is so full of themselves at this point that they think people will buy games at full price if they make it too difficult for them to get it on sale. You, me and everyone else knows that sales help sell games. Like the others have said, places like Steam and Nintendo will tell you when games on your wishlist go sale. But we're not talking about Steam, we're not talking about Nintendo or anyone else. We're talking about Sony here. If Sony knew what was best, they wouldn't have screwed up so badly on the store. If Sony wanted to give a price discount to sell games, they wouldn't have stopped issuing 20%-off coupons. Sony's hubris is getting the better of them and they think they can get away with selling more games at a higher price by cutting out the wishlist. They will eventually learn that's not how it works, but they're not going to learn that lesson until they fail at it first, unfortunately.