Apparently the game is MUCH more linear which is awesome.
How is that awesome? It is not awesome.
Having to go back and forth in Dead Space was the worst part. At least with a linear progression, it allows the devs to implement more environments and events.
It also obliterates the sense of exploration, which is usually a key ingredient in these RE-type haunted house sort of games -- or at least, the thing I tend to enjoy the most about them.
edit: Although now that I think of it, aside from a few specific examples, I don't think you really get to venture out into impertinent areas all that much in the first Dead Space, anyway. It's mostly just run here, get this, run back.