I noticed that once you customize the settings of a zone in Internet Explorer, the "Description" registry value in HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2 changes from:
"This zone contains all Web sites that are on your organization's intranet."
to
"This zone contains all websites that are on your organization's intranet."
Is this a bug or a feature?
If the latter, what's the purpose of that seemingly almost unnoticeable difference?
To further clarify the question, could this difference be used as a test to tell whether the zone has been changed from default to customized?
This isn't really a bug or a feature, but it is by design. Here is what happened:
The old Windows UI Style Guide said the right way to say it was "Web site". In the Vista time-frame, they completely re-wrote the style guide. As part of the changes, they decided that it should be "website". I don't know why they made this decision, but they did.
What's happening is, most likely, the original string is written by code that was developed using the old style guide, but when you change it you somehow trigger code that was developed under the new style guide.
I would certainly NOT rely on this behavior. If you want to know what settings are, use IInternetSecurityManager.