Is the shaking and rumbling a direct co-relation to the user's progress? If yes, the that is instant feedback for the user and can be considered a game element leading to a gamified site.
Mark LeBlanc's MDA framework (Mechanics, Dynamics, Aesthetics) is something you should take a look at for getting an idea of good elements for a gamified site.
Dynamics: (high level, conceptual elements. grammar of game. NOT rules. implicit structure)
Mechanics: (process that drives the action forward. verbs)
- resource acquisition
- win states
Aesthetics/Components: (specific ways to do things. nouns.)
- achievements - leaderboards
- avatars - levels
- badges - points
- boss fights - quests
- collections - social graph
- combat - teams
- content unlocking - virtual goods
The progress bar is a very good indicator, but does it have breakpoints or levels which can lead to unlocking of features or such? That can add a level of engagement.
Even though PBLs (points, badges, leaderboards) are a cliche, this is a good site for such a system. You can get badges for the stories you complete. The definition of badges will depend on the core direction you want to push your audience towards: competition, co-operation, generic fun, or something else.
Also, if you can make it a social experience, it would add a lot of value for the players. Make the objective of the site such that you need to co-operate to 'win'. Something what Stackexchanges do quite well.
And lastly, whatever you do, the system should always have instant feedback for the user's actions. I have explained a briefly how user behavior changes can be achieved using gamification in my other answer: How does Gamification change User Behavior?