I don’t know. I think I have to disagree about Rorschach having a giallo influence. He’s based on the Steve Ditko creation The Question, in the vein of Randian Objectivism (just cranked to an extreme in the case of Rorschach), and represents the blindness of moral absolutism and the loss of self to a perceived ideal.
As far as aesthetics, he’s certainly a tweaked version of the blank-faced Question, who in turn was almost certainly influenced by mask-oriented visual styles of early pulp and comic heroes such as the Clock, the Crimson Avenger, the Sandman, the Shadow, etc. (not to mention the much more obvious influence of Dick Tracy rogue, the Blank).
If there does seem to be a strong visual correlation, I think it’s more attributable to giallo and the character(s) that inspiration for Rorschach was drawn from both coming to rise in the late 20s and early 30s.
As for the Watchmen film, I’m going to be very cautious and try not to get my hopes or expectations up. I hope the rumors that were floating around a couple years back about the script having a completely different ending aren’t true; I can’t imagine anything would pack the punch of the original.