All of these early reviews are based on the Beta. I say wait after reviewers played the game for at least 40 hours and post their reviews (should be this weekend). Any reviews before 1/28/2010 should not be viewed as credible.
Granted MAG will be hit of miss for a lot of people but a good reviewer will put some time into the game before they go off and score the game like this. MAG is not like Halo or COD, it's more like an MMO for FPS the game is massive even in the beta.
Reviewers will need time to properly review this game.