I think it's for phones like the ROKR.
just installed iTunes 7 for Mac that i downloaded from apple and when i reached the final screen i clicked on "Customize" just outta curiosity and lo n behold... theres an option for "iTunes Phone Driver" thats grayed out...
here's a screenshot. i'll leave you to rumorize about it...
http://www.earlmisquitta.com/pics/itunes.jpg

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