Stay away from Mobile Talk still in the beta testing: Here is why,

Down loaded the Mobile talk on my blackberry and started making the international call, each time when I make a call it said connecting through Mobile Talk, interestingly after a month got a huge bill from my cell phone provide T-Mobile gues what those calls were going through the T-Mobile network instead of Packet8 Mobile talk network, Packet8 admits the problem but did not refund the money, Louzy customer support poor quality