There have been quite a few newspaper and online articles recently reporting that Wikipedia's's growth rate is slowing. These have taken a pretty alarmist approach. One of the articles linked to above is headlined, 'Is Wikipedia a slow death?'. Another hypothesises that an increase in 'editorial control' over entries may be putting people off.
The research comes from the Augmented Social Cognition Research Group at Palo Alto Research Centre (PARC), and is laid out on its blog. It's good work, and shows that the idea that Wikipedia's growth was exponential (as it looked for the last few years) was wrong. The level of editing activity has slowed in 2008 and 2009 (note: not the new-article creation rate - you'd expect that to drop anyway as the result of a backlog effect). The evidence is there, and it's robust and conclusive.
That doesn't mean Wikipedia is dying, though. The assumption in a lot of these articles is that would-be editors are either annoyed or bored with Wikipedia, and are deserting it. Having worked on a different-yet-similar collaboratively-driven editorial knowledge project, I think there's a better explanation.
Here's my hypothesis: Wikipedia is not dying but maturing. As it becomes a more comprehensive resource, glaring omissions and errors become fewer, so many of its readers no longer feel the need to alter it. They turn from active editors into users who have the power to edit, but do not necessarily exercise it.
The PARC research segments editors of Wikipedia according to how many edits they have made. It has found that the top two tiers (100-999 edits and 1000 edits plus) have grown their share of editing activity from about 55% in 2007 to about 60% today. Those who tend to edit less (call them the 'casuals') are editing even less; those who tend to edit more (what you might call the 'pros') are editing even more. Unfortunately I don't have the segment sizes, so can't tell if there are more or fewer casuals and pros, relatively or absolutely, than there were before. We'll have to wait for the data to be published at WikiSym 2009 in October.
Decreasing user activism need not mean users are getting fed up with a resource. It might mean they're becoming happier.
# Alex Steer (17/08/2009)