Apple's update is opt-outBy Ed Bott
In this gallery, I’ll walk you through how Apple offers updates to its software and how Microsoft does the same thing. After you see both procedures in action, you tell me who’s got it right and who’s doing it wrong when it comes to consent, disclosure, and treating customers with respect. Look at the evidence and decide for yourself.
When you install iTunes as part of setting up a new iPod or iPhone, one dialog box is labeled Choose iTunes QuickTime Installer Options. The third option reads Automatically update iTunes, QuickTime, and other Apple software. This option is selected by default. In other words, automatic updating is on unless you specifically choose to opt out of it by clearing this check box. There's no disclosure of what this option means.
For the full story, see What Microsoft can teach Apple about software updates