>> The exercise revealed numerous errors in both encyclopaedias, but
>> among 42 entries tested, the difference in accuracy was not
>> particularly great: the average science entry in Wikipedia contained
>> around four inaccuracies; Britannica, about three ...
> I'm astonished that a 25% difference is considered "not particularly > great".
I saw a followup to that that looked at the length of the articles. The Wikipedia articles were longer, which slightly more than closed the gap.
Wikipedia has more vulnerabilities than a traditional edited collection like Britannica, but it contains a rather amazing amount of information. Of course, no secondary source should be trusted very far.