I was looking through the recent news, and it looks like GameStop uped the price of the single figure packs to $13.99, a dollar more than than before. Although this isn't a huge diference, if your planning to buy all the figures later on, it could make a diference. Currently, GameStop is the only retailer to raise the price, so we'll see if other retailers plan to also raise the price.
http://www.gamestop.com/collection/disney-infinity