GigaOM

In its second-quarter earnings call this morning, AT&T highlighted the awesome growth of its wireless business, which surged 14.8 percent to $11 billion and accounted for roughly a third of its $30.9 billion in revenue for the period. The company also said that the 3G iPhone was selling twice as fast as the first one, which given the price cut, isn’t too surprising.

Equally unsurprising was the 10 percent rise in the number of smartphone subscribers over the second quarter of 2007 (AT&T is the sole carrier of the iPhone in the U.S.). And those users are surfing the web, pushing AT&T’s data revenue up 52 percent from the same period a year ago, to $2.5 billion. After adding 1.3 million wireless subscribers during the quarter, AT&T is still the largest cell phone carrier with 72.9 million subscribers. However, Verizon said yesterday it had added 1.5 million subscribers, so the iPhone exclusivity can only do so much.

The tethered world was a little less rosy, however. AT&T did add 170,000 new U-verse subscribers, bringing that total to 549,000; it also reiterated its goal of having a million subscribers by year-end. But triple-play services were down and broadband growth is slowing. Subscribers to voice, data and TV fell to 48.4 million from 49.5 million at the end of the second quarter of 2007. And AT&T’s total broadband connections now number 14.7 million, up 1.4 million over the same quarter last year but a mere 46,000 higher than the first quarter of the year.