According to MacDailyNews, a leaked AT&T memo shows us that it recently gets some good  achievement, such as On June 25th, you will see at that  the AT&T experienced the largest number of sent SMS messages per second over their network. In addtion,  It is also confirmed  this year’s Launch day 2009 that is described as the “best-ever sales day”. And all those milestonesis due to iphone 3GS ’s arrival

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IPhone 3GS Brings best-ever sales day For AT&T