Nextlink Expands to Nine Markets with Launches in Atlanta

RESTON, Va. -- Aug. 28, 2006 -- Nextlink Wireless, Inc., one of the nation's largest wireless spectrum holders, today announced an expansion in the availability of its service offerings with the launch of its broadband wireless solutions in Atlanta, Chicago, and Houston. Extending the service reach that began in Dallas, Los Angeles, Miami, San Diego, Tampa, and Washington, DC earlier this year, Nextlink is continuing to aggressively leverage the company's spectrum holdings in the 75 largest U.S. markets.

Concurrently, XO Communications announced that it will use Nextlink services as an alternative "last-mile" solution in these nine markets, selling Nextlink's broadband wireless services directly to enterprise and business customers By incorporating Nextlink's broadband wireless technology into the "middle-mile" of its network infrastructure, XO also will gain the flexibility to better serve its customers. (See separate XO story.)

"Today's announcement demonstrates that we are on track to meet our previously announced objective to launch services in twelve markets this year. It also illustrates the potential of fixed wireless services for applications beyond mobile backhaul," said Nextlink CEO Bob Beran. "XO's use of our broadband wireless solution for last-mile access and middle-mile leased line replacements validates the need for alternative access solutions in the carrier marketplace."

"Nextlink's broadband wireless capabilities offer the proven performance and scalability essential for the business-class services we provide," said XO CEO Carl J. Grivner. "Nextlink allows us to expand the footprint of customers we can reach, augmenting our metro fiber infrastructure. At the same time, we can reduce our network costs and time to deploy by not having to install our own wireline infrastructure or rely on the local incumbent carrier."

Nextlink services include broadband wireless access at speeds ranging from T-1 up to OC-12 over licensed local multipoint distribution system (LMDS) spectrum in the 28-31 GHz range. Nextlink's point-to-point and point-to-multipoint solutions work through line-of-sight connections of up to seven miles, and allow customers to seamlessly transition from legacy voice-only TDM networks to a next-generation, converged IP infrastructure.

About Nextlink

Nextlink, a subsidiary of XO Holdings, Inc. (OTCBB:XOHO.OB), provides broadband wireless services to the wireless and wireline communications service provider, business and government markets. As one of the nation's largest holders of fixed wireless spectrum, Nextlink delivers high-quality, carrier-grade wireless access solutions that scale to meet the demands of today's converged world of communications - supporting next-generation mobile and wireline voice, data and video applications. For additional information, visit www.nextlink.com.

About XO Communications

XO Communications, a subsidiary of XO Holdings, Inc. (OTCBB:XOHO.OB), is a leading provider of national and local telecommunications services to businesses, large enterprises and communications service providers. XO offers a complete portfolio of services, including local and long distance voice, dedicated Internet access, private networking, data transport, and Web hosting services as well as bundled voice and Internet solutions. XO provides these services over an advanced, nationwide facilities-based IP network and serves 75 metropolitan markets across the United States. For more information, visit www.xo.com.