I think it's probably just the ad company's idea to use a Mac. And, although a lot of Macs have been product placement by Apple on many shows, on some shows they're there simply because the producers/other hollywood people enjoy Macs, and put them there. I suspect it's just the advertising company, though... most use Macs, right?
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-Adam S ... PowerBook G4 (Mac OS X... the latest version, whatever it is, I've got it, dangit) and original iPod (iLove music, therefore iLove iPod)
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