In a report ranking subscriber satisfaction levels with cellular services, research firm In-Stat\/MDR has concluded that Nextel is earning top honors overall, followed closely by Verizon Wireless. Bringing up the rear, overall, is AT&T Wireless.In a report ranking subscriber satisfaction levels with cellular services, research firm In-Stat\/MDR has concluded that Nextel is earning top honors overall, followed closely by Verizon Wireless. Bringing up the rear, overall,\u00a0is AT&T Wireless.The researcher released the results of its 2004 Consumer Mobility Study, conducted via Web questionnaire, last week. The study aimed to measure how the carriers were faring in the wake of wireless local number portability, which kicked in last November.While AT&T Wireless customers ranked the quality of their network service the lowest (about 62% ranked it "good" or "excellent" compared with about 82% of Nextel customers issuing the same ranking, for example), AT&T did a bit better on customer service, taking fourth place and besting Cingular and Sprint.Of the "big six" U.S. cellular carriers, only Verizon improved its outlook for retaining customers. Verizon's churn potential dropped from 12% in an In-Stat study conducted last summer to about 10% now. At the other end of the spectrum, T-Mobile experienced the biggest increase in the likelihood of its customers to jump ship. About 17% of customers surveyed last summer said they were likely to change providers during the next year, but that figure has increased to 25% in the most recent survey.And while Nextel still can expect the lowest volume of customer churn (8.8%), its potential for churn is still rising; its likelihood-to-churn rate was at just 5.8% last summer.Of note: There was quite a discrepancy in the number of each carrier's subscribers that participated in the study. Only 34 respondents, for example, were Nextel customers, compared with 240 Verizon and 222 AT&T Wireless customers. The distribution for the other carriers: Cingular, 126; Sprint, 192; T-Mobile, 92. The smaller the sample, the less statistically valid the results (up to a point). In-Stat says a survey sample of just 34, for example, has a potential margin of error of plus or minus 17%. By contrast, the results of a survey sample of 100 can vary plus or minus 10%, and a 200-respondent sample can vary by about 7%.Meanwhile, why don't we conduct a small survey of our own? Drop me a line and let me know what's most important to you about your carrier service by ranking the following variables in order of importance to you, with "1" being top priority:1) Service price.2) Coverage (size of network footprint).3) Speed of network service.4) Quality of network service (e.g., quality of the voice calls, dropped connections).5) Availability of client devices to support both voice and data.6) Other (please specify).