Just read this in a transcript of Obama's acceptance speech.
quote:
You did it because you understand the enormity of the task that lies ahead. For even as we celebrate tonight, we know the challenges that tomorrow will bring are the greatest of our lifetime - two wars, a planet in peril, the worst financial crisis in a century.
It's interesting that the obsolete meaning of enormity meant 'vastness, hugeness'. If the word were decimate the mavens would want to go with its etymological and older meaning. Oh, the enormousness of it all!