AT&T posted strong second quarter earnings of $3.8 billion today, which the company said was aided in large part by robust growth in its wireless data services revenue.

AT&T's reported second quarter net income, which was up 31% from its reported income of $2.9 billion in the second quarter 2007, was highlighted by a 52% growth in wireless data services such as Internet, e-mail and SMS. In all, wireless data service revenues totaled $2.5 billion for the second quarter this year, up significantly from the $1.6 billion in wireless data service revenues that the company reported in the second quarter of 2007.

The biggest drivers for the wireless data revenue growth were test message volumes, which the company says tripled from the second quarter of 2007, and multimedia message volume, which the company says grew more than 170% from the second quarter of 2007. AT&T also added 1.3 million new wireless subscribers for the second quarter of 2008, and the company says that postpaid wireless subscriber churn was down to 1.1%, which is the lowest level of churn the company has ever reported.

Looking forward, the company expects the release of the 3G iPhone to fuel even more growth in wireless data services throughout the year. The 3G iPhone, which has been available in the United States for less than two weeks, has so far sold more than 1 million units since its release, nearly double the number of iPhones that the company sold during its first launch period in 2007.

"Mobility, broadband connectivity and integrated services that encompass voice, data and video are driving a new world of communications," says AT&T CEO Randall Stephenson. "The Apple iPhone 3G is a dramatic example of this transformation… this strengthens our wireless business and it reinforces our positive view of the opportunities ahead for AT&T and the industry."