I am not asking how many Bitcoin addresses there are. I am asking how many ARE being USED.
I mean, Im sure there is alot of empty Bitcoin adresses out there, but, how many of are people just creating a account and just saying: "Hm, I think I will buy it in a month or so." and then go onto never buy it, or perhaps some who create it but have no intent of using it?
Im asking if there is a way to know a rough estimate of how many people are holding Bitcoin?