Sprint Nextel’s widening fourth-generation wireless service, or Sprint 4G, launched today.

The mobile broadband connection can achieve download speeds up to 10 times faster than 3G service, according to Sprint.

Maui's 4G service started today, too.

That brings the market count to 27 metropolitan areas, including Baltimore, which was first, Atlanta, Chicago, Dallas, Las Vegas and Philadelphia.

Next year, Sprint expects to add Boston, Houston, New York, San Francisco and Washington, D.C.

Not yet, Kansas City. Not yet.

Sprint 4G runs on the WiMAX network being built by Clearwire Corp., of which Sprint is the majority owner.