Not only is the phrase "intergalactic civilization a turn-off, but the whole end-of-the-world trope could lead many listeners to picture SIAI wearing tinfoil hats. Get the public and the commentariat thinking about the more obvious threats first - such as massive structural unemployment. Once they learn enough, they will stumble upon the right evidence.
I tried to steer the discussion that way on NPR's website. No luck.
The NPR show All Things Considered did a short story on the Singularity, including interviews with Eliezer Yudkowsky and others involved with SIAI:
http://www.npr.org/2011/01/11/132840775/The-Singularity-Humanitys-Last-Invention