I believe from what I've seen that this game has a chance to nearly match 3 in terms of metacritic.  I think it will suffer a little as we've seen Kratos in HD now and the story is a little bit of just running in place since we know who will live and die it being a prequel and all.  However, it will be praised for MP and the epic scale the SP brings.  I say 89

88, sequels usually suffer when getting reviewed. every console god of war was better than the one before it, yet they got reviewed lower. now late in the gen nothing seems to blow people away. i guess an 88

91

Games don't get a lot of high scores at the end of this gen anymore.

This will be an excellent game but I wont reach the scores of GoW 3. The scale in GoW 3 is still unmatched and whilst I feel ascension will obviously match the scale of the previous game, it won't have the same impact.

The more interesting question will be the metacritic of the last of us. I have a feeling this will be one of the greatest games of all time. People are already comparing it to System Shock 2. 

Im hoping for 90-91 but realistically im guessing 86 motivation being: Some wont fancy MP, SP might seem as tedious after 5 entries and the story being somewhat done (no matter how amazing SSM might flesh out Kratos' blood oath story)

90 - 92

I dont really care. I know it will be a good game.

83, it is GoW but reviewers will find a way to be disappointed in the story or MP.

going out on a limb here

between 1-100

89
Though it will deserve a 94!