Cycling through dashboards can be done via a carousel. In order to turn on the carousel and change the frequency for cycling through views, the dashboards first have to be added. You can do this in the dashboard manager, which can be found under the wrench icon at the top of the dashboards page. Once you're in the manager, toggle on (the button will turn dark gray) the carousel option beside two or more of your dashboards. Save your changes to make the update.
Once dashboards have been added to your carousel, leave the manager. Click on the "Carousel (Off)" dropdown and select an interval for the dashboards to change views.