if there's ten million holders, price will go WAY up.
Who knows the exact number? I don't think that are millions. I am part of o site which is created more than 2 years ago (march 2013). This site accepted since the beginning only bitcoin as a fee to participate as a founder. It was made more than two years publicity to this site by everyone and now there are about 170 000 members. Are (mus be) mostly bitcoiners. If we can suppose that this program reached 50% of bitcoiners then the overall number of those cannot be more than 500 000 people. Maybe iI'm wrong and the bitcoiners grow every day but i don't think that are yet to much.