I put 'no' but I mean that as an average. I think currently as an average most people who own Nintendo consoles are rather casual. That is by no means a bad thing as it means Nintendo has created very accessible consoles. Of course there are still millions of Nindendo gamers who are core gamers.
I'm a PC gamer and it's the same situation. There are millions of core PC gamers, but we are simply outnumbered by people who play flash/facebook games ect because they are so accessible on any PC.