The lead story in the May 2006 issue of LJN Internet Law & Strategy is titled "Wikipedia Creates Concerns Aplenty About the Web's Reliability". Notwithstanding the title, the author (Shari Claire Lewis) discusses the broader issue of lawyers and web-based research.
Apparently, at least one U.S. Bar Association has taken the trouble to opine that lawyers doing web-based research are required to "take care to assure that the information obtained is reliable". In fairness, this ruling dates from 1998 – which is perhaps why the ruling seems startling today. Could anyone presume that internet-based research is magical and not subject to that most basic of rules – common sense?