The Encyclopaedia Britannica was once a sign of wealth and education. It looked good on the shelf, and impressed people that you had it. People would assume that you had read it, and that may or may not have been true. But if you just want information, there are cheaper sources.
I use Wikipedia quite a lot, and take a "trust but verify" attitude toward it. There was a study in 2005 that found Wikipedia to be as accurate as EB
http://news.cnet.com/2100-1038_3-5997332.html
If the article is non-controversial, I'm less skeptical about it, if it is controversial, I pay closer attention to the primary sources.