Update:
There is a new family plan for T-mobile that started July 31st, it's $49.99/mo. and 1000 anytime minutes shared. It is a Back-to-School promo. This plan does not have unlimited N/W's, only unlimited M2M. It is only available in certain markets.

Family Time - Back To School Rate Plan: Family Time - Back To School details


See More: T-Mobile Rates Update