ODF at 5 Years

"So what happened that made ODF possible? In one word, the Internet. Well, not so much the technology of the internet itself, but widespread access to the internet via the web. This enabled the open source movement as we know it today to scale. Although open source existed before the web, unless you were at a major university or research centers, sharing source code and working collaboratively on software was very difficult. But with widespread access to email, ftp, web, eventually version control, we had the tools needed to scale open source from small teams to large teams. And to write a competitor to Microsoft Word you need a substantial team."

http://www.robweir.com/blog/2010/05/odf-5-years.html