i realize the two are compared a lot here, but I wasn't really thinking of RE5 while playing it...they are very different games. RE made the transition to action game nicely (awesome, just baited another fistful response of shame), whereas Dead Space is still in this no-man's land between action and survival horror.
The controls aren't clunky enough and the health system isn't strict enough to artificially ratchet up tension. and the tasks don't require enough exploration to be survival horror, though I have my doubts about whether that's really a genre, but that's a different story. The action is just too easy, but not frequent enough. Taking out four of those alien/zombies at a time is no sweat. The fact that the plasma cutter shoots such a wide width makes shooting of limbs rather easy. but while you're doing your "run here, hit A at the glowing thing" tasks, they don't pop up enough. There aren't enough tense situations, only tense atmosphere.
It feels like EA was going for a casual horror game experience...the Prince of Persia/Assassin's Creed of horror, if you will. Though far better than either of those turds, of course.