Yeah, my kids and I played through it Monday night (I was able to find one at a local store I wasn't expecting it to be at - but for the full $50, so I may still try to get a Best Buy copy for $40 to exchange). It is fun, but very short and shallow - well worth the $10 though

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It could very well have just been a pack-in with the system at launch (or instead of Wii Sports as you suggest). Though I think BOTH should have come with it!
But, yeah, the reason is probably to fill the gaps between other game releases.
My two sons were having a blast with this though. They *really* like the tank game - I just wish there was a way to keep playing through the later stages as they invariably die before getting through about 6 of them (and then have to start over).
This is definitely better as a 2-player game. I haven't played the single myself, but I can tell you it is a lot of fun against another person.
Here's the IGN review:
http://wii.ign.com/articles/763/763835p1.html
They only give it a 5.5, which I wholeheartedly disagree with. It doesn't even follow from the text of the review. They fully explain that this is a $10 pack-in game with a remote and say it is worth it as such - but then give the low score. I don't quite get it. In particular, I disagree with their 4.0 score for the graphics. I think the graphics are a step above Wii Sports and are perfectly suitable. They wouldn't rate a 10 because of the simplistic style, but there's nothing WRONG with them, which is what I'd reserve a 4.0 for. I mean, even their comment after the graphics score doesn't match the score :lol:. I think the graphics in the laser hockey game are quite cool actually (the glowing paddles and the trails everything leaves).
They also pan the duck hunt game as short and boring - I agree, as a SINGLE player game. But play it with someone else and it is a whole different game (since you are competing for the targets and get to shoot the ones with their Mi on it while avoiding shooting your own).
Using the type of scale game review sites use and thinking of other game scores that I agree with (while keeping in mind this one costs $10) I would give it a 7.5. The problem with the 5.5 rating is that puts it in truly atrocious company and I don't think it deserves to be there. My big knock on it would be that there should have been at least twice as many games
