Wireless contributes approximately one-third of AT&T's pro forma revenues, and we believe that we have the industry's premier assets. Our advantage in wireless benefits our enterprise customers and supports our three-screen strategy for consumers — to integrate the wireless phone, TV and PC under a single, unified service.
Wireless revenue growth is driven by increased penetration of the mass market and by more demand for wireless access to e-mail and the Internet, along with the ever-increasing popularity of downloadable games, ringtones, instant messaging and video.
Nearly all of our wireless minutes are now carried on our newly integrated GSM network. With GSM technology, our wireless customers can make and receive voice calls in 190 countries and access data services in 120 countries. And in more than 165 U.S. cities, including 73 of the top 100 markets, we now offer high speed Internet access from wireless handsets and laptop computers equipped with 3G (third-generation) technology.
In early 2007, we announced the nation's largest unlimited free calling community. The AT&T UnitySM plan creates a calling community of more than 100 million AT&T wireless and wireline phone numbers, including homes and businesses.
AT&T continues to demonstrate leadership in wireless entertainment. We have expanded our offerings to include the most comprehensive mobile music subscription service offered by a U.S. carrier. With content available from online retailers, such as Yahoo!® Music, Napster and XM Satellite Radio, our customers now have access to the largest collection of music content available on a wireless handset.
AT&T also serves more than 3 million wireless business data subscribers, including 95 percent of the Fortune 100 and 80 percent of the Fortune 500 companies.
In 2006, we introduced several new products and services to keep businesses in touch with their on-the-go employees. The 2125 Smartphone and 8100 series Pocket PC come with integrated Wi-Fi, and our 8525 Pocket PC is the first personal digital assistant in North America to use an advanced broadband technology called UMTS/HSDPA.