Another company is reevaluating its Windows-based desktop requirements and is looking at Apple's MacOS X and Linux as alternatives.
Of particular interest in the article from Cnet is the comment from the AT&T CIO stating "There's competition; there's choice now. Any CIO would not be doing due diligence if they are not looking at their options now."
Of course, it wouldn't be AT&T's first bout with Unix if they decide to go with MacOS X or Linux. The company invented the UNIX operating system in the 1970's for use in their switching systems.