Wikipedia Articles Not Subject to Judicial Notice:

So holds an unpublished opinion from the New Jersey Superior Court's Appellate Division:

The common law doctrine of judicial notice is codified in N.J.R.E. 201. Subsection (b)(3) describes the rationale of the rule.

The purpose of judicial notice is to save time and promote judicial economy by precluding the necessity of proving facts that cannot seriously be disputed and are either generally or universally known. Judicial notice cannot be used "to circumvent the rule against hearsay and thereby deprive a party of the right of cross-examination on a contested material issue of fact." Because judicial notice may not be used to deprive a party of cross-examination regarding a contested fact, the doctrine also cannot be used to take notice of the ultimate legal issue in dispute.

... Wikipedia bills itself as the "online encyclopedia that anyone can edit." Anyone with an internet connection can create a Wikipedia account and change any entry in Wikipedia. In fact, Wikipedia warns readers that "[t]he content of any given article may recently have been changed, vandalized or altered by someone whose opinion does not correspond with the state of knowledge in the relevant fields." Thus, it is entirely possible for a party in litigation to alter a Wikipedia article, print the article, and thereafter offer it in court in support of any given position. Such a malleable source of information is inherently unreliable, and clearly not one "whose accuracy cannot be reasonably questioned."

The material that the trial court erroneously judicially noticed was a page "offered ... to establish that Bank One Corporation was purchased by J.P. Morgan & Company in 2004. Against this backdrop, counsel represented to the trial judge that J.P. Morgan sold the accounts, (including defendant's account) to his client Palisades Acquisition." This was relevant to whether the plaintiff actually had a right to sue over the failure to pay on that account.

Thanks to Victor Steinbok for the pointer.