This sounds interesting.
IMO, this would need to be a review after release, and ideally when the reviewer has finished, or got close to finishing the game. If you are talking about reviewing pre-release games, then that opens up a can of worms; needing a relationship with the publisher to get the pre-release software (very tough), needing a test machine to run it. I would have a hard time seeing how that would work.
However, a review within 2 days (Monday's maybe) of release (which is enough to complete most games, or at least get far enough to make an informed reveiw), by an AVF member would be fine. Reviews are there to help and inform the people who are undecided about getting a game - sure, a Halo fan isn't going to wait for the review of ODST 2 days after release, they'll have it day one. But for the vast majority, 2 days to see what a fellow member made of it, would be more than acceptable, and could save them cash, or convince them to get a game they may not have.
In many way, i think reviews on AVF would be more appealing than going to one of the usual outlets. For a number of reasons...
1) An AVF member reviewing a game will have nothing to 'gain' for a good/bad review, where as outlets more often than not have other motives. Reviewing games after release also means you don't need to set up deals with
PR or publishers, and as such, if a game is reviewed badly, you don't burn any bridges.
2) The person reviewing the game would have bought it with their own money. From experience, i can tell you, it's easier to give a game a decent review when you have not paid for it out of your own pocket. I think that would be a key advantage of AVF reviewing games.
3) Each game could easily be reviewed by 3 people. Thus giving a selection of opinions.
4) Because the people reviewing the games would be member's, and presumably posting on AVF anyway, member's would get a feel and idea of what the people doing the reviews are like. As noted, a review is a personal take on a game, not a de facto rule. One of the things i like about AVF, and the play and help threads is that you see posts on a game by member's who you believe are of the same mindset. Rather than a faceless person at IGN or what not. This just adds a personal edge to a review. I listen to a friends opinion of game more than IGN, because i know what that friend likes and doesn't like and i know how that relates to me. AVF reviews would be along those lines.
I will keep an eye on this thread and see where this goes...