The $28.1 billion Verizon Wireless is paying, including debt, points to a small profit for the private-equity firms. The buyout happened at a difficult time in the credit markets, and the banks who financed the deal reportedly ended up holding some of the debt on their books, rather than selling it. That put pressure on the buyout group to cash out.

Talks between Verizon Wireless and Alltel were reported Wednesday by CNBC and The Wall Street Journal. Based on those reports, analyst Craig Moffett at Sanford Bernstein said the deal could yield significant economies of scale.

"The consolidation of Alltel takes another step towards rationalizing and consolidating the U.S. wireless industry, something that must be viewed as a positive" from an investor perspective, he said.

He said regulatory approval was likely, since the industry is already viewed as consisting of four players: the national carriers Verizon Wireless, AT&T, Sprint Nextel Corp. and T-Mobile USA. The deal signals that "the days for a mid-sized, regional stand-alone wireless operator are numbered," he wrote.