The documentation for all Confluence versions states as description for the new page icon: "This page has been edited since you last viewed it. Click to view the page." (http://confluence.atlassian.com/x/AwAi)
We are currently using Confluence 3.5.13 and I can see that the icon will stay for quite a long time. It won't go away after I viewed the page.
So what is really the criteria for displaying the icon for a page?
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