International Unlimited Talk & Text with unlimted data (throttled to about 100 Kbits/sec after 100 MB in a month) - $60/month
International Unlimited Talk & Text with (throttled after 5 GB) - $80
The plans are each $10 more than the existing unlimited plans which do not include unlimited international calls and texts
The counties in the free calling area include Canada, Mexico, the Dominican Republic, most of Western Europe, Australia, New Zealand, China, India, Japan, Venezuela, Costa Rica, Panama, Uruguay, Columbia, El Salvador and Chile. Full list of countries covered (PDF).
Unlimited texting only applies to SMS text messages. MMS (picture or multimedia messaging is charged at the normal rate of 35 cents per message.
T-Mobile's regular rates for international calls are extremely high at $1.60 per minute plus domestic airtime to most countries so I guess these rates are a step in the right direction. However they are only cost effective for users who make a large number of calls and don't want to deal with calling cards.
I'd like to see T-Mobile bring their basic international rates down to reasonable levels such as the 2 to 25 cent per minute surcharge that Virgin Mobile charges to most countries.