I'm trying to decide which CMS to learn. My ultimate goal is to market a membership site with instructional videos so I need something powerful enough to do that. I'm not intimidated nor really care about the learning curve for Drupal or Joomla but if Wordpress is easier and powerful enough to do what I need, I'll use it.
I also want to develop a valuable skill that I can market (i.e. freelance design work) if I fail at my first IM endeavors.
So which of the three do you guys think would be best for me to learn. Which one is most powerful?