Has Sprint (NYSE: S) Nextel managed to heave itself back on track? The WSJ reports that the customer exodus from the country’s third largest network may be over, while the carrier may have a hit on its hands with iPhone copycat the Samsung Instinct, which since its June 20 roll out has sold out in some of its stores.

The news came to light apparently after Verizon Communication president Denny Strigl said in an investor meeting that their smaller rival had been improving in the last month—though not enough to hurt Verizon Wireless (NYSE: VZ).

Despite the two morsels of good news, Sprint still has a way to go in the fiercely competitive US cellphone market. WiMAX concerns may have been assuaged after its Clearwire (NSDQ: CLWR) JV, but questions remain over what Sprint is doing with Nextel.

The Nextel merger has been a bit of a disaster for the company, which is now mulling over whether to sell or spin it off. But Nextel would be a hard sell, notes the WSJ, which points out that the network not only “has major problems,” but Sprint would want the deal structured in a way that would let it also get rid of more than $5 billion in debt.

In the meantime, Sprint is at least trying to keep hold of Nextel users, giving them the ability to use the network’s popular walkie-talkie feature on new handsets using Sprint’s network—a move that analysts say clears the way to either let them finally monetize its Nextel customers, or to eventually phase out the Nextel network.

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