If you get past the fact that this a light-gun/on-rails shooter game, you will find a very good Wii horror title.
If you are fan of the original, you will probably get a kick out of this game. I loved the first 'Dead Space', so going back to the same areas was a nice trip down memory lane. The graphics are very sub-par compared to the more powerful Xbox 360/PS3 versions, but the game looks good for a Wii game. But there is where part of the rub is: this is Wii game. Because it's on the Wii, we have to settle for last generation visuals and it's an on-rails shooter.
While being an on-rails shooter doesn't necessarily make it a bad game, it was frustrating at times because I never felt immersed in the environment. And that causes a problem when a game is trying to scare you. To that point, unfortunately, this game is not very scary. It's certainly intense, but it doesn't conjure up the scares or overall creepiness that the first game did.
A nice thing about this game for people who have played the original, is that this is a prequel story. You play the role of a few survivors (you switch characters a few times during the story) from the original colony that found 'The Marker'. Even if you never played the original, the game never really makes you feel like you had to play that game to know what's going on here. Either way, this game tells a surprisingly deep and involving story for the type of game it is. In my opinion, this is the best part of the game as the story will have you hooked until the end.
Unfortunately, the end comes too quickly as this game isn't very long. This won't come as a shock to any fan of this genre (light-gun shooters), but it ends up being disappointing since the game is actually pretty good.
Obviously the biggest gameplay difference is the on-rails shooting that you will doing. Thankfully, the controls all work well as you aim & fire with the WiiMote pointing at the screen. You use the nunchuck to select your weapon, use your stasis powers and to reload. You also use the WiiMote to use your telekinesis powers, which brings up my biggest complaint with the game.
Other than the nagging problems that I mentioned earlier this game is great and very fun. But the game also has lots of items, ammo, audio logs, text logs, weapon upgrades, etc, scattered around the environment. The only way to pick these up is to use your telekinesis power. The problem is that the camera is on-rails and moves quite quickly, so if you aren't constantly paying attention to the background in the environment you are going to miss items. This is annoying when you are trying to concentrate on the story or the characters right in front of you. Most of the time you are using your telekinesis at any thing that is shining in the background instead of paying attention to the characters. It's aggravating, takes away from the story and adds to the problem of lack of immersion.
Even after that big complaint (and the other minor ones I mentioned), I really enjoyed 'Dead Space: Extraction'. It more fun if you have played the original and are interested in the 'Dead Space' universe, but this is one of the best on-rail shooters I have ever played. And I am not a big fan of this genre at all. The game looks good for a Wii game, the voice acting is solid and I was into the story. The shooting in the game works well with the controls and even though the game is too short, it's fun while it lasts. And Wii owner looking to pick up a light-gun game with a horror twist and a good story should check this game out.