ICANN has recently approved IDNs in 19 countries .The most recent approved IDNs are China,Taiwan,Sri Lanka,Honk Kong,Taiwan,Qatar, Thailand and Tunisia.
This is just a preliminary stage.However,it seems that the string review is the most difficult stage.
Other IDNs that have passed the ICANN preliminary stage are :
Bangladesh
Egypt
Palestinian Territory
Russian Federation
Saudi Arabia
Sri Lanka
United Arab Emirates