I just watched the documentary Life after People from the History Channel.  It was a very interesting idea.  Their concept was to document the progression of the planet if humanity suddenly disappeared.  The music and voice-over give it a distinctly creepy feel; which sort of makes sense given that it is discussing the planet without us.  The most interesting part about it though is watching some of the scientists they interview.  Their glee at how earth would restore itself when we are gone emanates from the screen.  It is unsurprising, especially in the case of the Greenpeace scientist they interview.  It is weird though, because if sentience is extinguished from the universe does it really matter if life goes on?