Rovio has revealed some details on upcoming changes to Angry Birds, and it sounds like the insanely popular game is about to get even better. First and foremost, they'll be implementing an in-app payment system called "Bad Piggy Bank." From the sound of things, it will be quite the elegant system - any purchases will be billed straight to your carrier, rather than to your Google Checkout account or credit card.
Coming with in-app purchases: the ability to buy the Mighty Eagle, which wipes out an entire level. Purchasing the eagle unlocks it permanently, but they'll limit use to just once per 24 hours - presumably to prevent people from beating the game by using the eagle for every level.
Next up is something people have been clamoring for since the game debuted: a paid, ad-free version. It will be interesting to see how a paid version works out for Rovio, as they're already raking in the dough from the ad-laden version. No word on when to expect it, or how much it will cost.