T-Mobile USA, the fourth-largest wireless carrier in the country, said Thursday it added 981,000 customers in the first quarter. Along with an acquisition, that brings its total to 30.8 million, according to The Associated Press:

"T-Mobile USA completed its acquisition of SunCom Wireless in February, which added 1.1 million subscribers in the southeastern United States, Puerto Rico and the U.S. Virgin Islands."

The report said that T-Mobile's growth means it is doing better than the next-largest carrier, Sprint Nextel, which has been losing subscribers and had 53.8 million customers at the end of last year. Meanwhile, Verizon Wireless added 1.5 million subscribers in the first quarter, and AT&T added 1.3 million and is still the largest of the four major U.S.-based carriers.

T-Mobile also finally turned on its high-speed, 3G network this week in New York City, with other cities to soon follow.

Score another one for Yahoo in its battle with Google for mobile search supremacy. Reuters reports that T-Mobile is switching from Google to Yahoo as its preferred mobile Web services provider in northern and central Europe.

The switch will happen at the end of March.

According to Reuters, Yahoo senior VP Marco Boerries said that adding T-Mobile as a carrier partner increases to more than half a billion the number of mobile users exposed to Yahoo services.

T-Mobile USA has been hit with a class action suit over alleged charges for text messages received by consumers who do not want the feature, RCR Wireless News reports.

The problem stems from the fact that customers are charged for both sending and receiving messages--even if the customer doesn't want them. Think about it: all those mobile text ad campaigns we've covered cost customers money if they haven't signed up for some kind of unlimited texting plan.

"T-Mobile refuses to disable the texting messaging feature on its customers' accounts, even when the customer has no interest in sending, or, more importantly, receiving text messages," stated plaintiffs representing customer Maria Detwiler and others. "Moreover, T-Mobile requires each of its customers who have not subscribed to one of T-Mobile's Messaging Value Bundles to pay for each and every unsolicited text message they receive."

Class action nails T-Mobile USA over texting services [RCR Wireless News]

T-Mobile USA enjoyed a rise in net new customers even as it reduced churn during the fourth quarter of 2007, RCR Wireless News reports:

"The nation's No. 4 carrier reported 951,000 net customer additions during the period, up more than 5% from the fourth quarter of 2006," the report said. "The carrier noted that 77% of new customers signed up for a postpaid plan, which was up from the 65% of contract customers during the third quarter of 2007, but well below the 87% posted during the fourth quarter of 2006."

That caps off a good year for the smallest of the four major U.S. carriers. T-Mobile added a total of 3.6 million customers during the four quarters in 2007, bringing their current subscriber base to 28.7 million. That's still well off the size of AT&T (66 million), Verizon (64 million), and Sprint (54 million), however.

T-Mobile USA Q4: adds 951,000 customers, cuts churn [RCR Wireless News]