Generally, I try to stay as far away as I can from website rivalries. As for myself, it all comes down to what site has the best signal-to-noise ratio, which seems to have the most knowledgeable contributors, and which is most usable.
In the beer-geekery web-world, the "big Kahunas" seem to be RateBeer and BeerAdvocate, and to me it's always been a toss-up as to which is a more reliable or useful source of information. (If I'm searching geographically, I tend to lean towards the increasingly-crassly-commercial Pubcrawler, which tends to focus more on the overall venues than the beer-centric reviews of the above two.)
Well, yet another beer site, RealBeer, came up with an analysis that, though imperfect and somewhat statistics-overladen, does tend to give food for thought over the rivalry.
My big problem with these sites (and Beer Advocate Magazine): It seems, too often for my liking, that these sites--or more accurately, the "personality," the vibe, the chatter, and the atmosphere of said sites--tends to push the "extreme beer" movement, while losing sight of the fact that far more customers--the customers that are the bread and butter of the brewers' business--drink the blueberry-wheats, the lighter ales, and the lagers that many reviewers at such sites would turn up their noses at. The noise of "extreme beers" tends to be out of proportion to the actual impact and market share, in my opinion.
What think you?