To add some perspective to how bleak T-Mobile USA's fourth quarter 2011 customer losses were, consider that today's announcement that the company had lost 510,000 branded contract customers was in fact a 28 percent improvement sequentially.

While today's subscriber numbers leave much room for improvement, T-Mobile still has a healthy 33.4 million customers at the end of the first quarter, a net gain of 187,000 compared to the 33.2 million customers in the previous quarter.

On the financial side, adjusted OIBDA was up 7.2 percent to $1.27 billion from the $1.19 billion reported in the first quarter of 2011. Branded contract average revenue per user (ARPU) in the first quarter of 2012 was up $2 from the year-ago quarter to $58, putting that metric more in line with other competitors.

Overall, net customer additions were actually up 187,000 in the first quarter, compared to 99,000 net customer losses in the first quarter of 2011

Service revenues were $4.4 billion in the first quarter of 2012, down 2.7 percent from the fourth quarter of 2011.

In an earnings call today, CEO Philipp Humm said that while improvements in customer losses were encouraging, the current trend is also "unsustainable" and needs to improve.

The question of the day is how to attract new customers without the iPhone, which has been the main source of customer additions for the company's competitors.

Humm stressed that 45 percent of T-Mobile's gross customer additions were unsubsidized, SIM-only customers who bring their own devices to the network. T-Mobile has recently been playing up its ability to host the AT&T HSPA+ iPhone on its 1900 MHz spectrum. T-Mobile hopes that a $4 billion network improvement program, which includes the rollout of an LTE network, will draw more defectors, phones in tow, to its network.

To that end, T-Mobile is revamping its image by transforming their popular spokeswoman from what Humm called "girly" to "edgy" in a new nationwide ad campaign that emphasizes faster data speeds. 

Humm said T-Mobile has little interest in the 700 MHz A and B Block spectrum that Verizon Wireless has said it will auction contingent upon approval of its bid to purchase AWS spectrum from a number of cable companies. Humm said the spectrum Verizon Wireless is offering is not interesting to T-Mobile because it is incomplete from a footprint standpoint and most of the A Block spectrum would interfere with Channel 51 public television, which resides at 698 MHz.

Humm declined to comment on rumors that T-Mobile has been in talks with MetroPCS about a possible merger between the two companies.