A few years ago, AT&T Wireless accepted a pile of money from NTT DoCoMo in exchange for a favor that the former would not be able to refuse. For buying an equity stake in AT&T Wireless, DoCoMo wanted the U.S. carrier to launch 3G UMTS technology in at least four markets by the end of this year.

At the time, it seemed like a pretty bold promise. Though DoCoMo launched UMTS in Japan more than two years ago, acceptance of high-speed mobile data and advance applications has not been nearly as robust in the U.S. as it has been in Japan.

This week, AT&T Wireless is making good on the pledge it made to DoCoMo, and though the U.S. mobile data market still would not be accurately described as robust, the competitive conditions are very different than they were even six months ago. Both Verizon Wireless and Sprint have begun building out national 3G networks using CDMA 1X EV-DO technology, which actually offers far better data rates than UMTS.

Some people might think that AT&T Wireless is merely trying to stay within competitive striking distance with this upgrade. However, once mobile companies get beyond speeds of 100 kb/s or so, it really doesn't matter much who has the fastest data rate.

AT&T Wireless should be able to offer many of the same services that Verizon and Sprint will be offering, and to customers, what matters most will be service capability and quality, not what the speedometer reads.

AT&T Wireless has indeed fulfilled a promise with its UMTS launch--a promise not to DoCoMo, but to its own customers.

E-mail me at doshea@primediabusiness.com