Don't get me wrong, the Medina is definitely interesting and a must see. That being said, be prepared to get lost and have lots of pushy shopkeeps trying to get you to buy from them.
We even had one person who followed us from in front, and when we turned away he backed up and came in front again. Eventually we got so lost that we were stuck following him.
Definitely visit, but be prepared for severe culture shock, and relax afterwards with some mint tea.