Looks like a good deal for $10 a month to call and text to 56 countries.
Calling landlines only.
Starting December 8th and available to most postpaid plans $49.99 or higher
T-Mobile will allow calling to 56 countries most popular long distance
calling destinations. For just $10 you can call any international landline
in these 56 countries and text to any mobile number worldwide.
Link: http://www.tmonews.com/2010/11/t-mobile-to-unveil-new-international-calling-plans/