How do you choose between Drupal, WordPress and Joomla? Part 1

Well... in one word, usability should inform your choice. I have noticed that WordPress punches far above its height in the CMS arena, especially with corporate sites.  Usability was the reason I started using WordPress as a CMS,  the same reason I was hooked with Mambo, precursor to Joomla, and later the ground-breaking  Joomla 1.5…