iPod touch FaceTime calling to be based on email addresses?

We've been assuming that the next iPod touch will get in on Apple's FaceTime video-calling action, but the open question has been how calls will actually be initiated without phone numbers, and BGR's saying it has the scoop: it's going to be based on email addresses. Registering an email address with the touch and FaceTime will let people videocall you using that address, but apparently calling an iPhone user will still involve knowing their phone number, which is a little odd -- but BGR believes the email-based system will extended to the phone eventually as well. It all sounds plausible enough, but we'll wait and see -- we've been burned waiting for Apple to add a camera to the touch before, after all.