If this sort of process was constantly happening among all intelligent species on all planets, we'd be in an empty universe (well, one with a lot of little blackholes anyway). The probability of running into other intelligent life "post anthropic principle" would be their practically non-existent measure times our practically non-existent measure.

Huh.

That's the most interesting explanation for the Fermi paradox in a while. (Not exactly plausible, mind you, but an interesting idea nevertheless.)