never said it wasn't but this game DSC came out in a very hectic launch window with a lot of very hyped games (MW2, L4D2, NSMBWii etc) one of which was another Zombie shooter. and add to that all the other rail shooters this year like DS:E, and the fact that it's coming up to xmas so a lot of gaming money was going to presents for the kids, and to top it off not much advertising. So all in all the fact that this title didn't sell well in this time isn't suprising. 

Woah, woah, woah, hold on a second there. Take a look at this graph:

http://vgchartz.com/swlaunch.php?reg1=All&game1=Dead+Space+Extraction+-+Wii[31932]&reg2=All&game2=Resident+Evil:+The+Darkside+Chronicles+-+Wii[32591]&reg3=All&game3=&weeks=12

Or this graph:

http://vgchartz.com/swlaunch.php?reg1=All&game1=Dead+Space+Extraction+-+Wii[31932]&reg2=All&game2=Resident+Evil:+The+Darkside+Chronicles+-+Wii[32591]&reg3=All&game3=&weeks=12&weekly=1

Those graphs tell a much different story than what you are trying to say in the OP. Resident Evil: The Darkside Chronicles is selling much better than Dead Space Extraction.

That said, I still think that light gun games are oversaturated on the Wii. Especially since FPS and TPS are so under-represented. It just burns out the shooter fans when a lot of the shooting type games all play similarly. Take a look at this graph for comparison:

http://vgchartz.com/swlaunch.php?reg1=All&game1=Dead+Space+Extraction+-+Wii[31932]&reg2=All&game2=Resident+Evil:+The+Darkside+Chronicles+-+Wii[32591]&reg3=All&game3=Resident+Evil:+The+Umbrella+Chronicles+-+Wii[6971]&weeks=12

http://vgchartz.com/swlaunch.php?reg1=All&game1=Dead+Space+Extraction+-+Wii[31932]&reg2=All&game2=Resident+Evil:+The+Darkside+Chronicles+-+Wii[32591]&reg3=All&game3=Resident+Evil:+The+Umbrella+Chronicles+-+Wii[6971]&weeks=12&weekly=1
I think he's talking more about this one but I don't think the latest week has been added

He is comparing the red line (RE: DC) to the blue line (DSE), not the green line (RE: UC).  I added that to show that I think the light gun genre is oversaturated on the Wii.  As you can see, the red line (RE: DC) is well above the blue line (DSE).

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