It is gratifying to read Jimmy Wales's thank-you message for having raised 7.5 million dollars to support Wikipedia. There is still a lingering disapproval of Wikipedia among librarians and educators. It is still not thought good enough to cite, but many of us recommend it as a starting point for a search, because the references and external links are generally very good, and save us a lot of work.
I've compared entries in Wikipedia and the Encyclopedia Britannica, and the EB, when it covers a topic, unquestionably wins on style. You sense a university lecturer at work. If you need an entry on , oh, say, the Boer War, the EB will have the better entry. But it is not free, and if you purchase the CD-ROM version, as I did, you often feel circumscribed. The entries don't lead you out into the greater Web with hyperlinks, as Wikipedia does. Admittedly, I have the 2004 edition of the EB.
And Wikipedia has so many articles that you will never find in another encyclopedia: entries on IBM mainframes, for example.