Well I bought GN and read it last night. Keep in mind that I don't read many comics or GN's (I will probably always think of GN's as comics, besides :P ).
The GN version was all right...and the movie does follow it fairly closely except for a few key points, seemed like...but Rorschach was a lot more interesting in the film - on paper he seems flat and dull, but on film w/a good actor the chr. was compelling, sad, amusing, and cringe-inducing. The Oxy-dude and blue-man were better in the GN tho. Anyway...it was interesting but if I hadn't seen the film first I probably would've put the book down half way through...not because it was terrible, but because I find the illustrative & narrative style chosen a bit boring, especially when "interrupted" by long txt-only stuff to provide more background. Distracting when it's supposed to be a GN, imo.
I'd probably like the actual story better in an all-words, novel form.