A recent study came out with the conclusion that most people can't tell the difference between expensive and inexpensive wine. In the study subjects were given wines to taste in various price categories and fooled into believing a lesser priced wine was more expensive. Most of the people stated that they were the happiest with the most expensive wines, which turned out to be cheap wine in disguise.
As with many studies I have to scratch my head and wonder what is the point. All this proved is that people are easy to fool if you make it look official. A much fairer and more accurate method to test whether or not people can tell the difference between expensive and inexpensive wine is to do a blind tasting. No information except varietal should be given and the bottles covered completely.
If you are curious as to whether or not you could tell the difference then click here.