If the argument is what it is exclusive and what not, the answer is very simple, and it's been already said. Exclusive is for a game only playable on one platform. If a game is playable in multiple platforms, even of the same company, automatically is not an exclusive. PC has to be considered the same as the consoles because it's a gaming platform too.
So, Starcraft II is a PC exclusive but Diablo III not. Halo Reach is an exclusive but Fable 3 not. The last of us is an exclusive, but Final Fantasy XIV not. It's very simple....