Ah, the Fermi Paradox. It is an interesting question, isn't it?
Yes. (See Wikipedia)
As I've previously noted ...
- I am not a big fan of the given-enough-time-if-it-happened-once-it's-inevitably-happened-more-than-once argument.
- I can't escape the feeling that this argument derives, at least in part, from the evolution-as-progress view (verses the evolution-as-unintended-consequences perspective).