Statistics have been published about Wikipedia and Wikimedia (PDF Here) .
The first lines are:
- According to comScore, Wikipedia is the fourth most popular web property, world-wide. In June, it served 327 million unique visitors.
- Wikipedia is available in 266 languages.
- It is continually expanded by approximately 100,000 active volunteer editors world-wide.
- The English version alone contains more than 2.9 million articles.
- All language editions combined contain more than 13.1 million articles.
- Next to English, the largest Wikipedia editions are German (911,000 articles), French (798,000 articles), Polish (600,000 articles), and Japanese (587,000 articles).
Resource Shelf : Updated: Key Statistics About Wikipedia and Wikimedia Foundation (September, 2009) « ResourceShelf