United States Cellular (USM) shares are down 1.66% after the company today posted preliminary results for the fourth quarter 2010 that fell below expectations. Shares are down $0.82 to $48.49. According to the company, it ended 2010 with approximately 6.1 million total customers. During the fourth quarter, it lost 10,000 postpaid customers and 11,000 prepaid customers. However, the company experienced higher than anticipated acceptance of its new, bundled Belief Project plans, with nearly 1.2 million new and existing customers adopting these plans. It also saw higher than expected sales of smartphones. Additionally, both the postpaid churn rate and ARPU for the quarter improved sequentially and year-over year. The company expects service revenues for the year ended Dec. 31, 2010 just slightly below the low end of the guidance range of $3.93 million - $3.97 million provided on Nov. 4, 2010. It also anticipates operating income for the year to be about 5% below the low end of the range of $200 million to $250 million. The company attributes the decline in its financial performance to the impact of certain promotions offered during the quarter in response to intense competition.