Anarkin, a poster on the prominent NeoGAF forum is claiming a PC version of Dark Souls is confirmed on this month's issue of German gaming magazine, PC Action. EvilOre, one of the board's moderators, is personally backing the claim.
The alleged PC version has been deemed the "Prepare to Die" edition. It features additoinal bosses, but is otherwise a direct port of the console versions (gamepad support included).
Which seems a bit strange since half the reason there's been such a resounding call for a PC version among is to take advantage of the higher performance a a computer could potentially allow. Still, I suppose good news is good news.
The games publisher Namco Bandai is actually holding a press event tomorrow, so if this all real, expect an official confirmation relatively soon.