Regulators Let Cingular Buy AT T Wireless The \$41 billion merger between Cingular Wireless LLC and AT T Wireless Services Inc. won approval from the Federal Communications Commission Friday, according to federal sources close to the agency. &lt;BR&gt;\&lt;FONT face="verdana,MS Sans Serif,arial,helvetica" size="-2"\ color="#666666"&gt;&lt;B&gt;-The Washington Post&lt;/B&gt;&lt;/FONT&gt;