Clearwire today announced that it's finally launching its 4G broadband service in Seattle in early December, as we first reported in August.

Clearwire partners Sprint and Comcast will simultaneously begin selling the service under their own brands.

The same rollout is happening in Philadelphia in the next few weeks and in Chicago in November.

"Consumers and businesses should expect to see additional network expansions throughout these cities, and a wide range of independent marketing and advertising initiatives," the company said in a release.

The 4G service is geared toward mobile computing and provides downloads up to 4 megabits per second for about $45 per month.

Clearwire is marketing the service with its "Clear" brand, while Comcast will sell it in service bundles as "High-Speed 2Go." Sprint calls it "4G" service.

Clearwire and Sprint will also be launching the service in Charlotte, Greensboro and Raleigh, N.C., and Austin, Dallas-Fort Worth and San Antonio, Texas, in November. They'll start serving Honolulu and Maui in early December.

Clearwire's national rollout of its 4G service began in Portland in January. It's going to succeed the current, pre-4G service that's been offered in Seattle and other markets.