I think that the reviews affect initial sales in the first week.
But, after that it is confirmation or non-confirmation from word of mouth...
My example this year is Transformers The Game... It got awful reviews. And did pretty good but not great the first week. But, it kept going after that and had decent legs for a movie game. This is because it is kind of fun... Short, not deep, but fun.
Also, some games get decent reviews but bomb on sales after the first week. Ratchet & Clank looks to be an example. First, week was good... This week well... The great reviews aren't exactly helping spur sales.







