Quite frankly, despite the fact that I raid a set schedule, I often feel like I'm significantly more 'casual' than many players who never raid at all. I know I play a lot less - I definitely do not log on every day, I don't run LFR unless I missed a boss in normal (because I want a shot at my Secrets of the Empire off of that boss) and I don't do pet battles, farm, or even do daily quests anymore. So with my roughly fifteen hours of WoW a week, 12 of it spent inside a raid and the other three futzing about older raids for transmog gear, am I casual or hardcore? And does it matter?
Ordinarily I'd explore the answer in the paragraphs to come. But frankly, the answer is no. It doesn't matter. It is so far from mattering that the light from it mattering won't reach us for fifty thousand years. What matters is finding out what players want to do with their time and letting them do it.