Verizon ( VZ) posted strong second-quarter numbers Tuesday, led by another impressive performance in wireless. For its second quarter ended June 30, the New York telco earned $1.8 billion, or 64 cents a share. That's up from the year-ago $338 million, or 12 cents a share, after a loss on the sale of the company's Iusacell stake. Revenue rose 6% to $17.84 billion. The latest-quarter numbers eased past the Wall Street analyst estimate; the Thomson First Call consensus called for earnings of 60 cents a share on revenue of $17.4 billion. "Verizon Wireless again extended its industry leadership with another outstanding quarter of profitable growth, including industry-record net customer additions," CEO Ivan Seidenberg said. "We also made headway in offsetting an anticipated decline in traditional wireline revenues with new revenues from broadband DSL, long-distance, data and enterprise services. Our investments in these areas are paying off, as we continue to transform our revenue mix." The strongest numbers came once again from the company's 55%-owned Verizon Wireless unit. The nation's largest wireless service provider posted 25% revenue growth, hitting $6.8 billion in quarterly revenue, along with a 570-basis-point gain in margins and a company record-low monthly turnover, or churn, rate of 1.45%. TheStreet.com reported Monday that Verizon Wireless had added 1.54 million subscribers in the second quarter, beating analysts' estimates. Verizon Wireless is a venture of Verizon and British wireless giant Vodafone ( VOD). The numbers offer the latest evidence that Verizon Wireless has been growing at a rapid clip. The June-quarter numbers surpass the 1.4 million new subscribers the venture added in the first quarter ended in March. Verizon Wireless now has 40.4 million subscribers. The reduction in churn beats the analyst estimate and comes as the company capitalizes on defections from AT&T Wireless ( AWE) and Cingular, which posted sluggish subscriber gains last week.