Drupal rocks! - some quick facts:
There are 9 projects (Linux, KDE, Apache, Eclipse, Perl+CPAN, Mozilla+Addons, Gnome, Drupal and GNU) that stand out as significantly larger - roughly 10 times - than any others.
954 people contributed at least 1 patch to the core of Drupal 7, over a 3 year development period. In addition to that, as of this moment, Drupal has some 8291 addon modules, a similar amount as the Perl CPAN archive. These facts don't fit nicely into any column in the above table, but underscores the size of the Drupal community - in fact, Drupal may be the largest open source project out there? The table shows the OHLOH numbers from 2010.http://openlife.cc/blogs/2010/november/how-grow-your-open-source-project-10x-and-revenues-5x