How big is Wikipedia, anyway?

http://en.wikipedia.org/wiki/Wikipedia:Size_in_volumes

If you could print every article on Wikipedia and bind them into books, how big would the collection be? Using a simple calculation, an article on the website (updated this month) shows that the English Wikipedia alone would have 1908 volumes of text only — no pictures. While the 4.3 million articles would occupy 10 library stacks, it’s not a major increase from 1907 volumes in 2010. The completion of just a single book in two years indicates that Wikipedia has already catalogued most of our communal knowledge.