VERIZON'S UNLIMITED CALLING PLANS VERIZON'S UNLIMITED CALLING PLANS Basic $99.99 All domestic roaming, long-distance, Mobile Web 2.0 and Internet access. Select $119.99 All domestic roaming, long-distance, Mobile Web 2.0, Internet access and unlimited messaging to anyone in the USA. Premium $139.99 All domestic roaming, long-distance, Mobile Web 2.0, Internet access, unlimited messaging to anyone in the USA, V Cast Video, VZ Navigator and Mobile e-mail. Source: Verizon NEW YORK  AT&T (T) and T-Mobile on Tuesday moved quickly to match Verizon's (VZ) $99.99 all-you-can-eat wireless plan, leaving just one big carrier — Sprint Nextel (S) — on the sidelines. Sprint probably won't stay there long, predicts Roger Entner, a senior vice president at IAG Research. "I think the likely outcome is that Sprint comes out with an unlimited plan that is (priced) slightly below" the others, Entner said. In a recent interview with USA TODAY, Sprint Nextel CEO Dan Hesse said he is considering an unlimited plan, though details are still being worked out as to how such a plan might be structured. On Tuesday, Sprint spokeswoman Leigh Horner said the company is continuing to evaluate rate plans but declined to elaborate. Horner said Sprint is testing two unlimited plans in a handful of markets, including San Francisco and Tampa. In those trials, Sprint is offering unlimited domestic voice, text and messaging for $119.99; another plan that also offers mobile broadband is $149.99 a month. Verizon's plan, unveiled Tuesday, marks a dramatic turn for the U.S. wireless industry, which has historically sold consumers big "buckets" of monthly minutes for a set price. Part of the industry's affinity for buckets owes to the fees companies take in from customers who exceed their monthly allotments. Those "overage" charges generate billions in profit each year. Now that the bucket has been tossed for high-end customers willing to spend $100 a month or more on wireless, value-priced variations may not be far behind. And that could be very good news for consumers, Entner says. Unlimited plans "are a really good deal," he says, particularly for people who dump landline phones. But price wars aren't so good for wireless carriers, which enjoy big profit margins and, as a result, legions of supporters on Wall Street. Concerned that a price war might be brewing, investors on Tuesday pummeled the stocks of AT&T, Verizon and Sprint. Verizon, the parent of Verizon Wireless, which isn't separately traded, fell 6.6% to $35.34. AT&T, whose wireless business also is not separately traded, saw its shares slide 5.3% to $35.89. Shares of Sprint, whose main profit center is wireless, fell 3.6% to $9.23. T-Mobile is owned by German phone giant Deutsche Telekom (DT). Entner, for one, doesn't think a price war is likely, mostly because the carriers know how bloody that would be. "Nobody benefits from a price war," he says flatly. But given the heated state of competition in wireless, he also allows that almost anything is possible. "They're like penguins," Entner says, referring to wireless carriers in general. "When one jumps into cold water, they all follow." AT&T is the USA's No. 1 wireless carrier with 70 million customers. Verizon is No. 2 with nearly 66 million, and Sprint, which has been bleeding customers over the past year, is No. 3 with 54 million. Conversation guidelines: USA TODAY welcomes your thoughts, stories and information related to this article. Please stay on topic and be respectful of others. Keep the conversation appropriate for interested readers across the map.