As promised, T-Mobile is pushing its MetroPCS brand into more markets. The company today announced 15 new cities, essentially tripling its presence to 45 markets. 

Beginning Nov. 21, MetroPCS expects to roll out more stores in the new operating markets, bringing LTE along with it. 

T-Mobile says it has now migrated more than 1.5 million MetroPCS customers to the T-Mobile network. All of those markets now have access to T-Mobile’s LTE network. 

Tom Keys, MetroPCS’ chief operating officer and executive vice president, said the move to more markets happened quicker than originally expected and puts the company in a postiion to capitalize on the upcoming holiday shopping season, as well as the first quarter of 2014. 

“Nobody wanted to over promise and under deliver,” Keys said, but addded that after seeing how things went in initial markets everyone was confident that the next markets could launch now, as opposed to mid-2014. 

Keys said there’s about 7.5 million customers still on CDMA handsets, but he said he’s confident that given current migration rates, most of those customers will see the value in moving to an HSPA/LTE-capable T-Mobile handset in the near future. 

When asked whether MetroPCS might consider a tablet offering, Keys says his company is looking at whether that kind of device is right for its customer base. 

“What T-Mobile has been able to do with Cupertino has been great,” he said, but questioned whether the MetroPCS base would take to a $200-$500 tablet. “That’s kind of a what-if game right now.”