Now that I'm reaching the end of my look at this first new season of 'Doctor Who' since 1989, it's time to look back at the series up to this point as far as the phrase "Bad Wolf" is concerned.
The online info-lode Wikipedia has this run-down of all the mentions:
"The phrase has turned up in every story beginning with the second one, with one mention in each of the two-parters. The confirmed sightings of "Bad Wolf" are as follows:
The End of the World: The Moxx of Balhoon mentions in a half-heard conversation to the Face of Boe the "Bad Wolf scenario."
The Unquiet Dead: When the clairvoyant Gwyneth reads Rose's mind, she says, "The things you've seen... the darkness.. the Big Bad Wolf!"
Aliens of London/World War Three: A young boy spray-paints the graffiti BAD WOLF on the side of the TARDIS.
Dalek: The call sign for Henry van Statten's private helicopter is "Bad Wolf One"
The Long Game: One of the several thousand television channels being broadcast from Satellite Five is BAD WOLFTV.
Father's Day: A poster advertising a rave in 1987 has the words "BAD WOLF" defacing it.
The Empty Child/The Doctor Dances: The bomb that Captain Jack rides at the end of the story is labelled "SCHLECHTER WOLF", which is roughly "Bad Wolf" (or "Worse Wolf") in German.
Boom Town: A nuclear power plant is dubbed the Blaidd Drwg project, which is Welsh for "Bad Wolf". The Doctor also noticed for the first time that the phrase had been following them around.
Bad Wolf: The corporation that runs the Game Station (formerly Satellite Five) is called the Badwolf Corporation."
Although they don't have it listed, there was another sighting in Parting Of The Ways - and I don't mean the melange of graffiti in the courtyard where Rose has her revelation.
While sitting with her Mum and Mickey in the chips shop, it can be seen written on a flyer hanging in the window right behind Rose's head.
(Check out the Wikipedia entry for "Bad Wolf". They also list the ancillary symbolic references to the term throughout the series.)
Being an adherent of this repeated meme (No, I'm NOT sorry for typing that!), I think the main problem in the end was that the pay-off was overwhelmed by the build-up. One reason so many 'Trek' shows fall back on "techno-babble" is that it's a safety net. If the audience doesn't fully understand what's going on, it's harder to feel let down by the splainin.
Still, it was a fun little puzzle and it might still have ramifications next season. And there is promise of a new puzzle dealing with an anagram that was heard this season. And for that, the prevailing rumor is that it was the word "Torchwood" as heard in the episode "Bad Wolf".