Being a "should" question makes this difficult to answer, but I'll try.
The superstition by the players actually has some basis in reality. The idea is to not inflate the event in the pitchers mind. It's doubtful, but at many points throughout the game the pitcher may not even be aware of a perfect game or no hitter is in progress. In any event, the idea that you could jinx it actually helps keep an atmosphere of normality around a pitcher who simply has a job to do.
Announcers and fans have no reason to abide by this superstition because the pitcher and other players should be largely unaware of what they are saying. In practice, many fans will openly talk about a no-hitter or perfect game while it's in progress (I've witnessed both at Kenny Rogers perfect game against the Angels in Arlington) and networks will often "cut in" to a game in progress while a perfect game is alive in the late innings. I've yet to see any restrictive etiquette around a broadcasters ability to talk about a perfect game/no hitter while in process.
Knowing that baseball fans can often be as superstitious as the players themselves, some may have a problem with this. You can't please everyone though, especially not those who don't live in reality.