http://swoopyboigame.com
I'm no marketing expert and have actually not pushed hard on marketing the game. So have been surprised with its success.
If you were in my position what would you do to push the game reach to a new level?
It sounds like you've found the holy grail: self-marketing game.
Your biggest challenge now is to not fuck it up.
Focus your effort on improving game performance and new features.
Let players market the game for you by offering an amazing experience.
Have you considered something for us Web users? :)