Facebook has been busy working on its Credits virtual currency plans lately — but what exactly is it doing? Developers have told us conflicting answers. Some say that the company is going to force every application to use Credits as the sole virtual currency, while others say that Facebook has not made any such decision. We’re also hearing conflicting reports on how profitable Credits are turning out to be so far. Note: Most developers we spoke with asked to remain anonymous in order to preserve their relationship with Facebook.