There was a book written on this very topic a few years back, but the name escapes me at the moment.
Alchemy of the Heavens?
http://www.amazon.com/exec/obidos/tg/detail/-/0385472137/qid=1091212578/sr=8-1/ref=sr_8_xs_ap_i1_xgl14/104-0276543-3117500?v=glance&s=books&n=507846
the book was
"the rare earth"
written by brownlee and another u of wash prof
an amazing book.
They go thru all the arguments why complex life is so rare. This is my solution to fermi's paradox.
The Torah.
I believe it was "privelidged planet", sorry if somebody already told you, i don't feel like looking,.