Some comments are really funny, like for example the "i will pirate unless this or that...". We all know that this is just your excuse, you will pirate it anyway. Let us be honest here, if you don't like a game, why play it? And if you like a game, have fun with it for many hours without paying a cent to the ones who made it, you are a thief of their labour, plain and simple... No amount of lame excuses like "it was on GFWL" will alter this simple truth.
Now on the topic itself, i believe that Dark Souls will be a commercial failure for PC. I find it amusing that the incompetent staff at Namco believe that by listening to silly petitions like that means "they care about their fanbase". Japanese developers in general do not know what "listening to their fanbase" really means. They follow a simple formula "if something sells, milk it to the death while investing on it as less as possible". That is why even japanese developers think their games are garbage today...
It takes little intelligence to figure out that the persons that signed this petition are almost certain owners of the console version of the game, or at least the majority of them. People that are interested in JRPGs and japanese gaming in general are never exclusive PC gamers by definition. People that get out of their way to support a certain game almost always have played it. And even if they don't have the console version, then their opinions are even more worthless: It is easy for someone to say they want something to be available, since they are not binded to that opinion, they are not risking any money or anything... This doesn't mean they will buy the thing, they simply want to have the option to buy it...
Since fans of its genre probably already bought it, then Namco will have to target PC gamers who have no interest in console gaming, and we all know that they face strong competition there. From games like Skyrim for example. So they will not have the sales the believe they will have, unless they make this port something really special and not a typical sloppy console port.
And if this game is a failure, then PC gaming will take another hit, since they will blame piracy again and will stop porting games again... But we all know the reason PC gaming is dead isn't because of piracy, but because on a PC they can't sell dumped down games for an arm and a leg... PC gamers tend to be more capable of understanding when a game is a rip-off and that is a big no-no for publishers like Namco... Do you believe that a game like Ridge Racer on PS Vita could be sold for that price on a PC? Think again...