Mysterious giant crater appears in Siberia

Well now, here's an interesting tidbit of news: http://www.youtube.com/watch?v=NMlSJlWcJ7k&list=PL53nfRA55GqdZ9W0xd7utWBOvwbZvJvsS

See videos of giant crater on link above.  Much speculation about it -- no one really knows what it is, but it sure is Big.  So many mysteries, so few answers.