"Stop me if you've heard this one before ..."
I actually really like this as an intro. I like the implicit challenge to the editors to keep coming up with something we haven't heard before (not that I think that they need to be kept on their toes). I love the tease of suggesting to the reader that they might have heard something before, then blindsiding them with a cunning twist or a truly fantastic tale: I think it plays nicely to readers' expectations of traditional fantasy and PodCastle's obvious facility for coming up with something more interesting.
"I believe in (oblique reference to story). In a few minutes, so will you."
Please no. Don't tell me what reaction I "will" have to a story: even if I grit my teeth and keep my thumb away from the Stop button when I hear the phrase, I will instinctively look for reasons to have the opposite reaction. I would rather listen to the stories with an open mind, and something like this would prejudice me terribly.
Here's a simple one, based on fantasy's territory in non-future imaginary worlds:
"It could have happened like this..."
Although I'm not happy with the extra hurdle this puts before suspension of disbelief (that it
didn't happen like this), it seems preferable to PseudoPod's grating insistence on the truth of its fictions. Ambiguous versions seem to get the worst of both worlds:
"Maybe it happened like this..."
"I heard that this is what happened..."
But maybe it could be adapted each week to the story and the tone of the intro.