This new feature builds on Gmail's Priority Inbox technology, which tries to select and highlight the most urgent e-mails in of a person's inbox.

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Conceptually, this is simpler than Priority Inbox, since Gmail is only trying to sort messages into general categories rather than figure out which people are more important to you than others. (I've been using the new version for a few days, and the sorting seems to work really well).

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Tuesday morning, Gmail users should see a red "New Features" link in their inbox that will let them enable Priority Inbox.

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