No, Bungie are not accountable at all. Most likely, the exclusivity deal was struck between Sony and Activision anyway and there is nothing wrong at all with it. The fact is, Sony have paid money so that their customers can enjoy additional content sooner and at no extra cost, so Xbox owners who say they aren't getting what they paid for are just plain wrong. Sony have done this to gain market share. That's what businesses do, compete to gain an advantage by offering a better product/deal to their customers. Would you be happier to hear that Microsoft and Sony had colluded to fix prices and rip off their customers? I for one am happy that they are still genuine competitors and not a cartel.