I don't know how much the rest of you know about console gaming culture (I'm an expert), but honor and shame are huge parts of it. It's not like it is in pc gaming where you can become successful by being an asshole. If you screw someone over in consoles, you bring shame to yourself, and the only way to get rid of that shame is repentance.
What this means is the console gamers, after hearing about this, is not going to want to purchase FFXIII for any system, nor will they purchase any of Square's games. This is HUGE. You can laugh all you want, but Square has alienated an entire market with this move.
Square, publicly apologize and cancel FFXIII for steam or you can kiss your business goodbye.