The answer is simple.
Reviews on GAMING websites are written by GAMERS, therefore the games that are skewed towards the 'hardcore' crowd are going to score much higher. This oppinion is very 'gamer' skewed.
Expect high scores for Metroid, Smash Bros Braw and Mario Galaxy because they are all core gamer games.
Games like Singstar, Wii Play, Buzz, Wii Sports, Big Brain Academy aren't made to appeal directly to the harcore gamers and therefore they get lower reviews because of this.
Sales are not directly related to reviews, and the fun you have cannot be taken directly from reviews... so many times have a played a game after seeing it get a crap review from one of the big sites and loved the shit outta it... it don't mean nothing it's just their oppinion.
Halo 2 got massive scores - c'mon tell me that wasn't bought.
I remember the shenmue review on Gamespot, I remember that the reviewer found the game boring as trite, and that's fair enough if he found it boring then that's his oppinion.
PLUS for these guys who spend all day reviewing games and writing game news the actually fundamental gameplay and game construction has to be very 'tech' and up to their high standards.
IGN gave Big Brain Academy a 5 for graphics, it had no true 16:9 widescreen for the mini-games but i've played that game and it looks good and clean it might not be a polygonal masterpiece but for what it is trying to do the graphics are great, there are no ugly jaggies, the colours are rich and pretty... I just think it's stupid to review a game on those merrits when it clearly isn't trying to be something it's not.
