Seeking Alien Trash
I was interviewed by Seth Shostak (minutes 15:45 to 23:00 of this show) on possible observational consequences of my game theory model of interstellar colonization. (Previous posts on this here, here, here.)
The bottom line is that even if an alien colonization wave once passed this way, our astronomical theory and observation abilities are probably still just too weak to see the telltale signs of such a wave.