we play trivia in stevens point wis. and they just asked that question. The answer is Mel Torme Seth i heard that commercial and i thought ella fitzgerald, so i looked it up. she does a version although i doubt its the EXACT version as the one on the commercial seing as most of the songs on commercials are doctered up to sound more... interesting.
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:> Who does the version of It don't mean a thing (if it ain't got that swing) in the GMC commercial