I would be surprised if #1 was the case. Given the amount of volume of traffic that this app will generate, the traffic for identifying a rapidly signing in Message.app will be pretty unique and easily blockable by Apple.
Additionally, I know that recent efforts in the hackintosh community had problems with Message.app because the latest protocols incorporate being able to access the serial number of your machine (or something along those lines). Apple goes through some extensive hoops verifying that access to OS X -only and iOS-only services really does come from their devices.
Additionally, I know that recent efforts in the hackintosh community had problems with Message.app because the latest protocols incorporate being able to access the serial number of your machine (or something along those lines). Apple goes through some extensive hoops verifying that access to OS X -only and iOS-only services really does come from their devices.