Eight months after launch, Citizendium is still evolving but has not reached a critical mass of participation. The project is a wiki encyclopedia led by Larry Sanger, which distinguishes itself from Wikipedia with "gentle expert oversight" and the use of real names by its contributors. It received a flurry of media attention in October and November 2006, but generated only modest publicity for the site's public opening in March 2007.
The site is now averaging less than 200 article edits per day and has approximately 2400 live articles; by comparison, Conservapedia ("the conservative encyclopedia you can trust") generates about 1000 article edits per day and has produced about 15,000 articles since going live in November 2006. Because of its real names policy and verification process for new users, however, Citizendium has virtually no vandalism and little disruptive behavior. According to Citizendium's statistics page, new article creation has held steady at about twelve per day over the last two months.
Between July 12 and July 19, the project added about two new "Citizens" per day. The influx of new users has fallen considerably each month since March. Citizendium's registration process is much more demanding than that of many other wiki encyclopedias, and is currently done via email. On the Citizendium blog Sanger recently reported a backlog of dozens of account requests; nearly two dozen accounts were added between July 20 and July 22. Sanger has promised a 24-hour turnaround for future account requests. Delay between account request and account creation likely accounts for the significant disparity between the number of new accounts added each month and the number of users making their first edit (in recent months between one half and one third of the number of new accounts).
Though intended as an open content project, Citizendium has yet to decide on an appropriate license for its original content. In policy discussion on the Citizendium forums and on-wiki, some users favored the GNU Free Documentation License (GFDL) (which would make original Citizendium content compatible with Wikipedia), while others preferred a Creative Commons license, possibly one that excludes commercial use. There has been little discussion about licensing since early June. Citizendium requires content derived from Wikipedia articles to be listed under the GFDL, with a link back to the Wikipedia source.
Citizendium began as a "progressive fork" of Wikipedia, from a Fall 2006 database dump, and many of its articles still bear the imprint of their Wikipedia origins. In January, Sanger ordered the deletion of all Wikipedia articles that had not been substantially modified by Citizens. However, after the unmodified Wikipedia articles were purged, many users added up-to-date Wikipedia content without acknowledging the source. This has created a challenge in identifying all Wikipedia-derived content, some of which has changed substantially from its original form.
Citizendium features a process of approval, by which articles are certified as factually correct and balanced by individual editors or groups of editors with relevant professional expertise. As of July 22, when most of the research for this article was completed, Citizendium had thirty-one Approved articles. Of these, seventeen are wholly original Citizendium content, five are identified as containing Wikipedia content, five are derived from Wikipedia articles but unattributed as such (or were unattributed until recently), and four contain similar content to their Wikipedia counterparts but were released separately to Citizendium by the main contributors.
As on Wikipedia, the production of Citizendium original articles ranges from single-authorship (often with minor copyediting by others) to coordinated collaboration among a number of writers. One of the project's strengths is in the life sciences; twelve of the thirty-one Approved articles fall under the Biology Workgroup, with two more classified as Health Sciences. The first Approved article, Biology, is a concise and well-written historical introduction to the field of biology, but is perhaps better compared to Wikipedia's History of biology than the field/discipline-oriented Biology. Life is a collaborative project like "Biology"; this article is one of several that are longer and more heavily referenced than the corresponding Wikipedia articles (see Life).
Other Citizendium originals that contain more prose and/or citations than Wikipedia's include: Ancient Celtic music (see Celtic music); Contraception (medical methods) (see Birth control); Frederick Twort (see Frederick Twort); Horizontal gene transfer (see Horizontal gene transfer); Infant colic (see Baby colic); and Tux (see Tux). One Approved article, Telephone newspaper, has no Wikipedia counterpart.
Citizendium articles, and Approved articles in particular, represent a different editing philosophy than that of high-quality Wikipedia articles. In general, Citizendium editors strive to be more concise, and to present each article as a whole work rather than a jumping off point for related articles. Citizendium also encourages less use of inline citations ("a more sensible approach to citing sources"), explicitly relying instead on the knowledge and authority of its named editors for anything that is "common knowledge among experts". As Citizendium aims for gentle introductions rather than exhaustive discussions, the prose is more informal than Wikipedia's.
For example, Complex number is shorter than Wikipedia's Complex number, with a much simpler structure. It includes a numerical example of complex arithmetic, but leaves out many of the specific applications and properties discussed in the Wikipedia article. Overall, it is geared toward someone who is completely unfamiliar with the concept, whereas Wikipedia's article is organized so that more advanced readers can easily jump to the specific details they need.
Forks of Chiropractic and Vertebral subluxation—spearheaded on Citizendium by practicing chiropractor D. Matt Innis, who had also worked on them as Dematt on Wikipedia—evolved considerably from the Wikipedia versions of Chiropractic and Vertebral subluxation. Most of the exact Wikipedia prose has been replaced in these two articles, except for short phrases, though much of the original structure remains. However, they are listed as Citizendium originals because of the central role Innis played in the Wikipedia versions. Many of the citations were trimmed out over the course of the articles' Citizendium life, and a number of editors worked on them in addition to Innis. The Approved version in each case represent a compromise between a chiropractor and several physicians.
The five Approved articles that are acknowledged as Wikipedia-based (Barbara McClintock, Chemistry, DNA, Dog, and Wheat) have all changed since forking from the Wikipedia versions (mostly ca. September 2006), but Wikipedia has outpaced Citizendium in terms of added citations in each case since the fork.
History of Pittsburgh, primarily written by Wikipedian Tom Cool and uploaded to Citizendium by Cool, was split into two articles (Pittsburgh before and since 1800) and received some copyediting, but the content is largely unchanged from the Wikipedia version.
The remaining five Approved articles were originally based on Wikipedia articles, but were unmarked as such. They retain varying degrees of the original prose and structure. For one of the articles (Félix d'Hérelle), the lack of attribution was a clerical oversight (since corrected), as the versions before Approval were correctly marked. The main author of John Franklin claims that all remaining Wikipedia prose was originally contributed by him (former Wikipedian Profrap); however, some prose by others (for example, from this contribution by Blainster) remains in the article. Unattributed content from Wikipedia's bacteriophage also appears in the Citizendium version.
Finally, unattributed forks of Metabolism and RNA interference (see Metabolism and RNA interference) had similar outcomes to the five attributed Wikipedia articles: they have expanded and changed, but less so than the Wikipedia versions (both of which are now Featured Articles). Particularly substantial work went into both versions of "metabolism", the last common ancestor of which was hardly more than a stub.