People just read too much into it. For one, the art style itself is not that great, at least from my point of view. The animation was decent, but the coloring of the anime was far too focused on red and black for its own good. I realize that the read and black theme was supposed to signify blood and darkness, but it was overused. The characters themselves experienced little development, especially the police girl, I believe her name was "Victoria". Alucard himself hardly during the series, if there was any change at all. It also ended short, and left far too many questions unanswered, such as what happened to that Exorcist that Alucard fought on one of their missions.
Also, it has in part to do with the fanbase. Commonly I see a bunch of psuedo-rebellious teenages who are obsessed with Hellsing purely because of the fact that it has vampires in it, and it is so "dark", and it proves that "dark isn't always bad", and so on and so on. More of that angsty teenage jive what just gets my blood boiling.
Th</FONT></FONT>e anime is good, but just very overrated.
Another series I like, yet dislike a good portion of the fanbase.