Actors or astronomers?

There has been a lengthy discussion at Asymptotia, one of L.A.'s smarter blogs, about the burning issue of whether or not the narrators at the Griffith Observatory planetarium shows should be conversant with astronomy or just have nice voices. There are arguments posted on both sides. The debate has been going on since October, and has included a Times Op-Ed piece by Margaret Wertheim of the Institute for Figuring.