From experience, most Hellboy fans I know like a certain style of comic books, mostly pulpish stuff,. I also noticed that 9 times out of 10 they follow creators instead of characters.
In other forums the Hellboy thread usually diverges to other topics such as movies, other similar style comics (The Goon, Rocketeer, etc), statue and merchandise collecting, etc.
Also, with so many books Mignola related books coming out every month (BPRD, Hellboy, Baltimore, Witchfinder, Lobster Johnson and Abe Sapien) I was wondering why more people don't discuss it here...
I do believe Hellboy has one of the most rich universes in comic books, there's a lot to discuss!