T-Mobile's CMO Mike Sievert on Monday elaborated on his iPhone 5 "gangbusters" comment, telling CNET it had one of its biggest ever weekends. Without sharing precise numbers, Sievert said the carrier sold more iPhones than its "really ambitious internal goals" projected.

After years of battling without one of the most popular handsets out there, the iPhone's arrival finally puts T-Mobile on level ground with the other three big carriers. It still doesn't have the kind of robust LTE network you'd find through AT&T or Verizon, but T-Mobile's recently revealed Uncarrier initiative should do well to attract budget-conscious consumers. If anything, it introduces a new element that competitors are taking note of.

Sievert on Friday said there were lines outside of T-Mobile's 3,000 locations around the U.S., highlighting just how much fans were anticipating the iPhone's arrival. The goal now for T-Mobile will be to attract new consumers to its network, and avoid shedding customers to the bigger competitors. T-Mobile's excuse of not having the iPhone no longer applies.

Initial interest, it seems, has been big for T-Mobile, which is good news all around. And even better is the fact that many of the carrier's new iPhone owners signed up for a new two-year contract, according to Sievert. But what of the iPhone 5S in June/July? Hopefully there's no availability lag with new iPhone releases.