My question is why everyone is so worried about what constitutes a casual or a dedicated player. What does it matter which one you are? Just play it how you like and use the time that you have.
Personally I would say casuals playing most of the time not on a fix time schedule and rarely several hours (3hrs+) in one session. You are playing a lot, if only work and university are the only compareable time consuming activites on a normal day. I would classify you as semi-hardcore to hardcore if you hold the 5hrs a day over a longer time than a month or so.
I wish I had the luxury of saying "I can play 5 hours a day + week-ends".
I'll probably have 5 hours per week-end and 1-2 hours now and then during the week.
I'll hit 60 about the time Phase 5/6 comes out. :D