Add favicon alerts for pinned sites.
When you pin a site who can alert the user for an notification, there is no visual alert in the favicon showed in the tab bar. This is very unhelpful in pinned sites, where there is only the favicon showed.
For example, if I pin Facebook.com, if there is a new message or notification, the favicon in the tab bar should show any kind of alarm. If I pin Hotmail.com, there should be some kind of alarm when a new mail arrives, etc.