I think it's a bit over 150 million users. The community is slowly growing up, but will reach a big number in a few years (probably 400-500M users). The more Bitcoin users the community gets, the more people will hear about it. Because it's like an infinite pyramid: you tell your friends about it, they tell their friends about it and so on.
That's far too much. I don't think that is true. The amount of people is growing, but this is by far to much.
I guess it's about millions, not hundred of millions but just a few (i.e. 2 or 3) million.