i think you did not catch the essence of the post. Time spent on Twitter is a cost for enterprises and affects productivity. Whatever the numbers are - so far is true! And saying still Twitter is far more interesting than Solitaire does not solve the issue. But look at the bright side : exposure in minutes is what sets the value for advertising in all media- tv, radio, blog and twitter. Main difference is that Twitter provides content generated by its own users.
I met Marc a few times. Great man, so knowledgeable. He will be missed - my prayers goes to his family. I agree with your post...we should enjoy life much more.