As you can see, Skyrim on the 360 alone has a bitover 3 times as many preorders as Dark Souls on XBOX and PS3 combined. Also interesting to note is the drastic difference between platforms, notice that the PS3 version has well over twice as many preorders. This indicates that the XBOX community seems to have a decreased interest in the game, due to not having Demon Souls most likely, hurting the sales even more.
Of course it's only fair to note that something of even more difference has happened with Skyrim, having only about a third of the preorders on PS3 as it's 360 counterpart. Even then, the PS3 version of Skyrimhas about as many preorders as both versions of Dark Souls, and that brings us to the final conclusion: Skyrim is winning by4 times as much.
In terms of which will be the better game, that's completely subjective.
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