Personally I think IGN does a very proffessional job, and give fair unbiased reviews more often than not. I also think they hit close Gamerankings averages fairly often, so they seem to be a nice middleground. They rarely praise a game up and down that doesn't deserve it and alternatively they aren't particularly hard on games that don't deserve it. But if they critisize a game such as lair or redsteel, you know there is an obvious problem with the game, and approach with caution. I think their reviews are well written (not contradictory garbage that could be written by 8th graders like 1up and often times gamespot), and informative. They tell you what you want to know without spoiling things for you. If I want a review IGN is usually the first place I check.

Though quickly Gametrailers is becoming another favorite of mine. 

My end all is usually Gamerankings or Metacritic (usually Gamerankings) when I just want a quick look at a game. If I want something more detailed and feel like reading, I like IGN. If I don't feel like reading Gametrailers video reviews are generally really good.

I use IGN and EGM, but given the fact that sometimes the reviwers give low scores because they don't like a particular style of gameplay or some specific game element I have to read them rather than look at scores to get the whole picture. Additionally, if a game is getting cryptic scores from the few places I check, like if one place praises it while the other lambasts it then I will check gamerankings to get a wider scope.

I used to also watch X-Play and I trusted their reviews the most, but once they started being ridiculously stupid on the show and putting that chat scoll (that coveres up games during the review) I gave up on them entirely.

ign and gametrailers, also a little bit of gamespy and gamespot before it went down the toliet

gamespot user review average score...

Gamerankings and IGN now. I used to look at Gamespot almost exclusively, but I found myself increasingly disagreeing with them.

If its a game i am iffy on then IGN but if its a game i just want i dont bother looking at the reviews and judge myself.

IGN, but I enjoy Gametrailers reviews, their video style is great, and the reviews are fair.

IGN

User Reviews >>>>...>>>> Pro Reviews

Pros are just normal people anyway so there is no reason to give them any more credibility than anyone else (ie user reviewers are just as good until they are proven otherwise).

User reviews are better than pro reviews for three other big reasons.

1 - They are not being paid! (no pressure on them so they can tell you exactly what they think)
2 - The sample size is much larger (thousands of reviews vs. 10 pro reviews)
3 - You can track a reviewer that is most similar to yourself by reading his/her past reviews and comparing them to your own quickly and easily.

The only problem with user reviews is that about half of them are plain garbage (biased or childish reviews) but you can skim through those quickly so its not a big issue.