The magic glue that keeps all this together is the Cloud, in this case acting as your alter ego, a digital representation of you and your stuff: all those preferences, settings, privileges, programs, subscriptions, documents, photos, videos, music, and backup services.
Feature-wise, preferences and other desktop settings imported easily with Firefox Sync's shared password system, and the unfortunately named "Awesome Screen" is the new home page shown above, from which it's fairly simple to launch your preferred sites.