Arkane CEO Raphael Colantonio had some news regarding the upcoming Dark Messiah patch for Voodoo Extreme:

"We're currently fixing a lot of the stuttering that happens with Dark Messiah on some hardware: We're modifying the way we're accessing some of the audio and precache files. A patch will soon be released for both the Retail and the Steam version. It fixes a lot of issues, including a few scripting bugs and some performance [issues]. We are really sorry for the problems some of you have had with the game, and be sure we're fixing them all."

The game is running just fine for me, even though my computer is slightly below the minimum requirements. But a gain in performance would be more than welcome during some of the most hectic sequences of the game.