While you may be correct that the best reason to upgrade to Vista is the improved security, that was clearly not how the product was primarily advertised to the general public. People were shown ads with amazing Aero eye-candy, and told that Vista was the way to get it. When purchasing a computer that says "Vista capable," it's a reasonable assumption for a non-technical user (to which those ads were targeted) that buying a "Vista capable" computer will deliver the most prominently advertised feature of Vista. I'm not saying it's a bulletproof case, because the small print was there, but it's rather self-contradictory to advertise Windows Vista as being easier than ever for novice users, but also expecting same novice users to understand the system requirements of a GUI that is an optional component of an OS.