Oh, there's no question that it's distinctive, unmistakable, and flashy. At level 60, you weren't a priest worth knowing until you got your Benediction/Anathema. It was a badge of office. I had that darn thing for well over a year, so much so that my character was hard to recognize without it.
In fact, in Karazhan, you can tell instantly if any of the adds are the holy priest or shadow priest. Why? The holy priest has Benediction; the shadow priest, Anathema. (And the MS warrior has an Arcanite Reaper, for those who remember the days when that weapon ruled the world.)