Is number of users/percent of addressable market going up, or just spend from the same existing userbase?

(I did some strategic search-on-page-ing, but didn't find anything addressing it, and as a non-gamer, the breathless excitement about the topic was exhausting)

I get the general impression that 'casual gaming' (which takes me back to the bad old days of Zynga) was bringing in new users by the truckload, but I don't really feel it "in the real world"