Ho trovato le seguenti domande frequenti su sito web di Apple :
Why can't an upgraded version of Microsoft Windows XP or a full version of Microsoft Windows XP that does not include Service Pack 2 (SP2) or later be used for installation?
An upgraded version of Microsoft Windows XP cannot be used because you are required to validate your copy of Windows by inserting an original Windows CD, but there is no way to eject the first disc until after Windows installation is complete and the Boot Camp drivers from the Mac OS X 10.6 DVD are installed.
E quindi mi chiedevo se avessi due unità DVD collegate a un MacBook Air, potresti installare Boot Camp usando una versione di aggiornamento di Windows 7?