Renminbi(yuan) is circulated to 1400million people (china)
Rupee is circulated to 1289million people (india)
Euro is circulated to 742million people (europe)
dollar only circulated to 320million people.. (america)
sorry america is not that big.. only the media spoon feeders think america is great
based on population dollar is 4th.. based on number of countries using it daily.. euro wins by far
I heard that you could withdraw US dollars from ATM's in Cambodia and pay in USD anywhere in the country. That surprised me a bit but US Dollar is not only used in the US. There might be even more countries that actually use it as a secondary, unofficial currency. Whereas Euros and RMB, as far as I know, are only used in their respective countries (and yeah, of course in trading or in casinos and such international stuff, for instance when I was in Macao they only accepted euros, US Dollars and Hong Kong dollars in casinos, no Macao dollars).
$11M for 1BTC is a sweet dream that's not going to come true, imo, to stay on topic.
Dollar is multinational currency, judging currency potential by number of natives of said country is rather ignorant perception - it is like judging language potential only by its native speakers.
As far as I can tell English is the common language of the world - at least for now and Dollar is the most renown currency.
It will be probably respected and accepted in majority of 2nd and 3rd world countries with no problem. While I doubt anyone will accept yuan outside China.
