how many country of the world now accept btc? 
I do not know exactly how many countries allow the use of bitcoin in the world, I think most are large countries with advanced technology to allow the use of bitcoin. Now this is just some of the countries that accept bitcoin to exchange national currencies. Because indeed there are some intelligent people or people who understand about the technology that will boom in the future, so the bitcoin trust from there, resulting in a community and finally the birth of exchange that can help us more to earn easy money. But if indeed you want to exchange money might be able to use the site most recommend with money exchange to us dollars. i.e. btc-e