Wine reviews are in many ways different from reviews of audio equipment. They are admittedly purely subjective, they are a product that is in a state of change, they are for products that are of limited quantity for a limited time of availablity, and there is no guarantee of uniformity of product, each bottle of the same wine from the same vintage can be different. The reviewers have access to a vast number of different wines you could never possibly come close to tasting yourself unless you are in the business. Their ratings are based on early samplings of products that are often undrinkable at the the time they are tasted and are based on experience guessing where they will likely go when they mature enough to drink and enjoy. These guesses can often be wrong and so revisiting the same wines years later can result in very different ratings from the same reviewer.
I find it impossible to make any intelligent decisions about buying wine without professional advice. When I take a guess based on reputation, I'm almost always wrong. The two sources I rely on and the only ones I trust are Robert Parker (The Wine Advocate) and Wine Spectator Magazine. I discount the opinions of everyone else. In general my taste preferences have been more in agreement with Laube and Suckling (WS Magazine) than Parker's but there are exceptions. It will be interesting to see who was right about 1990 Pichon Lalande when I finally get around to opening some, Suckling who loved it or Parker who hated it.
According to the Bordelaise themselves, every current vintage is the greatest vintage in history. Parker who revolutionized wine reviewing was the first to give thumbs down to famous makers' efforts that were mediocre or worse. He explains in many of his books what he calls the incestuous relationship that existed between Bordeaux winemakers and British wine merchants. The notion was that if you didn't agree with the experts, you just didn't know what you were talking about and an ignoramus (now that's one thing wine and audio have in common.) I've learned over the years again and again that I pay WS and WA for advice, merchants for wine. Merchants will also tell you anything to move product off the shelves. There are a lot of games in the wine industry between distributors and retailers.
Parker has been called the greatest critic of anything in the world. He's claimed to be able to identify by taste and smell alone over 100,000 different wines including their vintages. Unfortunately Parker's newsletter and Marvin Shankin's Wine Spectator Magazine have pushed up the price of the world's best wines from moderately priced to absurd (another similarity with the audio industry.) It's actually been Parker's numbers that have the most influence. If he rates a particular wine very highly you know the price is going up. How lucky for me I stocked up in the late 1980s and early 1990s when prices were still within my range. I'm only sorry I didn't buy even more back then. The best ones are just starting to come into their own.