Sprint lost 644,000 Nextel contract customers and 376,000 Boost customers, though Sprint was able to lure 521,000 of those departing subscribers over to its CDMA network. There are now 2.1 million iDEN customers remaining, which means Sprint has a rocky two quarters ahead before the network goes offline completely.

On the CDMA side of the house, Sprint added a net 401,000 contract customers and 525,000 prepaid customers, but the Nextel exodus still resulted in a net loss of 337,000 customers. Sprint now has a total 55.6 million mobile connections.

Sprint activated 2.2 million iPhones (as opposed to sales), which is just a quarter of the volume done by dominant iPhone distributor AT&T, but Sprint was able to use the device to lure in more customers. Of the 6.6 million iPhones sold in 2012, Sprint estimated that 40 percent were new customers, meaning Sprint isn’t just upgrading its existing subscribers to the iPhone. The carrier also said that it sold more Samsung Galaxy S III phones than any other carrier.

Sprint reported a loss of $1.32 billion in the fourth quarter off of revenues of $9 billion.

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Of those 8.6 million iPhones, only 16 percent of their owners are new to AT&T, meaning the device is really more a tool for it to keep current customers by upgrading them from other phones or earlier iPhone models. But keeping customers happy with iPhones has benefits as well. AT&T’s contract churn rate (the percentage of its customers that depart every quarter) fell to 1.19 percent from 1.21 percent in last year’s fourth quarter. That puts it just a little bit behind Verizon Wireless, which has the most enviable churn rate in the industry at 0.95 percent.

AT&T added a net total of 780,000 new contract subscribers while increasing its overall number of connections by 1.1 million. Verizon added 2.2 million new subscribers, meaning Verizon grew at a much faster rate. But AT&T and Verizon were much more evenly matched in smartphone performance with Verizon activating 9.8 million devices. The difference was primarily in the mix of devices. With only 6.2 million iPhone sales, Verizon leaned much more heavily toward Android devices.

AT&T’s iPhone prowess over the years largely explains its huge smartphone penetration. Seven in 10 contract customers now has a smartphone on the AT&T network.

On the wireline side, AT&T added 192,000 U-Verse TV customers and 609,000 U-Verse broadband customers, giving it 8 million U-Verse customers in total. In Q4, the number of U-Verse broadband customers surpassed the number of DSL customers, a measure of DSL’s decline as well as U-Verse’s popularity.

Like Verizon, AT&T’s bottom line suffered due to higher pension costs and the expense of recovering from Hurricane Sandy. It posted a Q4 loss of $3.9 billion off of $32.6 billion in revenues. AT&T’s LTE network now covers 170 million people, but in 2013 its capital outlays will increase as it fills out its 4G footprint to cover 250 million people and engages in the massive undertaking of transforming its old-school telephone systems into an all-IP network.

This post was updated at 2:18 p.m. to add more details on AT&T’s financial and operational performance.

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Data usage is now swinging strongly towards LTE. Though only 23 percent of Verizon’s 98 million retail devices have LTE radios, they now account for nearly 50 percent of all data traffic.

Verizon recorded 2.2 million total net subscriber additions for the fourth quarter in its wireless group, while on wireline it racked up 144,000 new net FiOS Internet and 134,000 FiOS video customers. Those gains resulted in record revenues of $30 billion for the quarter and $115.8 billion for the fiscal year. Despite that, Verizon’s fourth quarter loss widened to $4.22 billion due to rising pension costs and the financial impact of Hurricane Sandy.

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Last year’s fourth quarter is the current record holder at AT&T. Then Ma Bell activated 9.4 million devices. All of the same factors that drove such huge sales last year are again in place. Most notably Apple kept with its adjusted iPhone launch schedule, which with the iPhone 4S was moved from the early summer to fall. That means AT&T will reap the benefits of a new iPhone release and the traditional Christmas sales boom both in the same three-month period.

There may be incentives for consumers to invest even more heavily in the iPhone this year as opposed to last. The new iPhone 5 not only has a new design and new iOS 6 features, but it is the first Apple smartphone with LTE capabilities. AT&T could also an uptick across its LTE device portfolio due to the huge expansion of its network. At the end of 2011 AT&T had a meager 15-city footprint, but today it offers its new 4G service in 109 markets covering 150 million people.

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Sprint CEO Dan Hesse

For the first time in six years, Sprint’s aging Nextel and wireline businesses didn’t overwhelm all positive gains from its primary CDMA business in its quarterly results. Sprint was helped along by 1.8 million iPhone activations, leading to big gains in revenue per subscriber and boosting its total wireless customers to a record 55 million. Still, Sprint is anxious to get rid of the Nextel albatross and spent a good of its fourth quarter financial earnings call detailing its plans to shut down the iDEN network.

Sprint plans to winnow down its total cell sites by 44 percent, from 68,000 towers to 38,000 over the next two years, said Steve Elfman, Sprint president of network operations and wholesale. In 2011, Sprint plans to decommission 9,600 towers by culling cell sites from many of its markets, maintaining its Nextel and Boost Mobile services while shutting down excess capacity. Sprint has started publishing maps on its website identifying which sites are targeted for the scrap heap.

Sprint is simultaneously building its new network architecture, called Network Vision, which will support its current CDMA network and future LTE network across its myriad of spectrum bands. Elfman said Sprint’s infrastructure vendors Ericsson, Alcatel-Lucent and Samsung have already begun work on all 38,000 Vision sites and plans to bring 12,000 of those towers online in 2012. The commercial LTE service will launch by mid-year in 10 markets. Sprint CEO Dan Hesse revealed two more of the 10 today, Kansas City and Baltimore, adding them to the previously announced Atlanta, Dallas, Houston and San Antonio.

The launch of Vision, combined with the shedding of the iDEN network burden, will fundamentally change Sprint’s cost structure for the better, Elfman said. He estimated that the operational and capital investment costs of delivering a gigabyte of data will drop by 50 percent. The cost of delivering a voice minute will also be halved, he said, though it wasn’t clear whether Elfman was talking about those savings coming from its CDMA 2G network or its future implementation of voice over LTE.

If Sprint can really halve its data delivery costs, it may be able to breath a second – or even a third – life into its unlimited data plans. Sprint is the only nationwide operator that hasn’t given in to the pressure of capping or throttling data, but enormous demand for mobile broadband services has to be threatening that strategy. The longer it can keep up with its customers’ unlimited use, the longer it can maintain its key competitive advantage against AT&T and Verizon Wireless.

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IDC found that Mac sales in the U.S. had climbed by 31 percent compared to last year, but that despite that strong growth, sales hadn’t kept up with increases in the industry at large. Cheap Windows machines helped create a banner year for the PC side of things. Gartner came up with slightly less impressive numbers for Apple during the quarter, with a growth rate of 23 percent.

That’s quite a difference, and represents a 40,000 machine gap between the figures found by the two companies. It’s a large enough gap to affect whether Apple falls under or above the average gain among all companies listed in the rankings. By comparison, PC makers HP and Toshiba had incredibly strong years, growing sales by 45 percent and 71 percent respectively.

In a quote from Computerworld, Gartner analyst Mikako Kitagawa explains what Apple’s doing wrong to miss out on the promising industry numbers, and its a tune we’ve all heard before:

The U.S. market last quarter continued to be very price driven. If a company is not in the low-priced market, it’s absolutely difficult for it to increase market share. And Apple did not do as well as others in share because of its prices.

Netbooks and cheap laptops are flying off the shelves, in other words. That being the case, the growth numbers might not mean as much to Apple as they might otherwise. If companies like Toshiba and HP are making their gains on the backs of underpowered machines of questionable build quality, and ones that might also have lower profit margins than Apple’s line, then it might not be growth that Cupertino is interested in. I maintain that we’ve yet to see the fallout of selling so many cheap machines so quickly. Wait a couple years till they start showing significant failure rates, then we’ll see how long-term growth is affected.

The general recovery of the PC industry is good news for Apple, though, even if it didn’t reap as many of the direct benefits as some of its rivals. The bottom line is that people are once again willing to spend money on consumer electronics, and computing devices specifically. The climate is a much better one in which to introduce a tablet than it has been in recent memory.

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