When it comes to current events, I think the advantage that Wikipedia has over traditional encyclopedias is not authoritative but rather referential. With most articles (such as historical events or scientific breakthroughs), Wikipedia converges to a pretty authoritative treatment of the subject and can be more accurate than a singe-source encyclopedia. With current events articles, Wikipedia provides a starting point for further reading (including via the citation pointers) whereas a single-source encyclopedia may be out of date and completely devoid of content on the subject.