No, not true. 98 isn't a 100. Several games have made a 100, not by ONM but by other, more professional/unbiased reviewers. I'm waiting for the Famitsu 40/40 that I have a hunch Skyward Sword will get. If not because it is a great game, then because it is a Zelda game.
Furthermore, I don't agree with ONM giving SS a 98. The game deserves a 100, with all the reasonable hype and justified hype it is getting. Really, I'm waiting for the perfect scores to roll in.
GameFAQs...accurate/neutral? No, I'm sorry. On GFAQs, you have bashers and fanboys, for the most part. I would know – I've sent in a review for Kingdom Hearts Re:Coded and it was accept; though the thing that changes everything is the review was entirely biased. Similarly, Coded got a really low score (I think it was a 3/10) by a user named won't say his name and THAT was accepted, yet clearly biased and without reason behind it. Many similar things have happened with Star Ocean 3, SO2, SO4, even Batman Arkham Asylum. GFAQs isn't accurate. I wouldn't even vouch for Metacritic...