Here it is halfway through 2007 -- the basketball and hockey seasons are behind us, and the sleepy summer heat is settling in. The lull before second-quarter earnings gives us a good opportunity to review company performance, so we'll step up to the plate and take a look at U.S. wireless-services provider Sprint Nextel (NYSE:S). Let's see how the company has performed so far and what may be on the horizon for the balance of 2007.

First-half review
While operational pains at Sprint Nextel have continued, the stock has rebounded nicely and given investors a roughly 10% return since the beginning of the year, up a couple of points on the S&P 500. As seen by its increasing churn, the company has been battling a slide in customer retention the last several quarters following the merger between Sprint and Nextel. And though it still generates the highest average revenue per user (ARPU) in the industry, it is losing ground to competitors AT&T (NYSE:T), Verizon Wireless, which is a joint venture between Verizon Communications (NYSE:VZ) and Vodafone (NYSE:VOD), and even Deutsche Telekom (NYSE:DT), a subsidiary of T-Mobile.

Operational issues aside, Sprint Nextel is still pushing hard to capture new customers, such as with its new, iPhone-poaching Upstage phone. The company has also continued with its next generation network plans that are based on the WiMax standard. To this end, it signed a major deal with Disney's (NYSE:DIS) ABC Television Group to bring ABC video content to Sprint Nextel phones.

Second-half prospects
To get a peek at what top investors think of Sprint Nextel's prospects, we can tap the Motley Fool CAPS database of investor opinions and ratings on the stock. CAPS players are still generally bearish on Sprint Nextel, giving the company a subpar two-star rating out of five stars.

I believe that the worst of the internal quality problems are behind Sprint Nextel. Management has taken several steps to address customer satisfaction issues and is exploring several options to increase value to shareholders. But like many CAPS investors, I'm not so sure Sprint Nextel's stock is beaten down enough to make it an attractive turnaround play. The market has already been buying into the turnaround story over the last few months, which seems a little early to this Fool as the company still faces formidable competition.

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Fool contributor Dave Mock could survive on ice cream sandwiches if he had to. He owns no shares of the companies mentioned here. He is the author of The Qualcomm Equation. Vodafone is an Inside Value recommendation. The Fool's disclosure policy is more refreshing than a cool breeze.