really but what about the whole concept of being thousands of miles away from the majority of the human populace,
thats a extremely standart concept for horror.. some would even call it a cliché
and the face that in both games your playing against muataed humans,
again, an extremely standart concept, still not a valid comparison to bioshock
and with the audio files, ect
doom 3 (and im sure more games) had those before bioshock did.
the gameplay style in both games is entirely different, and dead space tries to get out that "claustrophobic" feeling.. though in my opinion, none of the two is really all that scary.. they startle, but they're not genuinely scary like doom 3 pr silent hill 2 are for example.
as a action game, dead space does ok, but there's a lot of cheap attacks enemies tend to use (like the small bugs)
though dont take this all as fact, my only experience comes from the demo