AT&T will beat one of its LTE goals on Sunday when it turns on its mobile broadband network in six new cities and begins selling the LTE-capable Samsung Galaxy Tab 8.9.

AT&T will light up its LTE network on Nov. 20 in Indianapolis; Las Vegas; Oklahoma City; Charlotte, N.C.; San Juan, Puerto Rico; and Kansas City, Mo., and Kansas City, Kan., which are being counted as one market.

The launches will bring the service to a total of 15 markets, meeting AT&T’s market commitment for 2011. By the end of the year, the network will cover 70 million people.

The network expansion is scheduled for the same day AT&T will begin selling the LTE-capable Samsung Galaxy Tab 8.9. The debut of the Android-based tablet brings AT&T’s total number of HSPA+ and LTE devices to 24, beating its goal to offer 20 devices compatible with its upgraded HSPA+ service and LTE network this year.

The tablet has an 8.9-inch 1280 x 800 pixel display and comes equipped with a 1.5 GHz dual-core Snapdragon processor, 16 GB of internal memory, 1 GB of RAM, and front- and rear-facing cameras. The device retails for about $480 with a two-year contract.

Customers who buy the tablet between Nov. 20 and Jan. 7 can get a free Samsung Galaxy S II Skyrocket or Galaxy S II smartphone but must sign a two-year agreement with a monthly data plan.

The announcement of the new LTE tablet came yesterday, the same day Amazon began shipping the $199 Wi-Fi-only Kindle Fire. The Fire is said to already be the best-selling item on Amazon.com. Amazon also began shipping its new Kindle Touch and Kindle Touch 3G today, ahead of its previous Nov. 21 launch date.