rough brainstorming towards creating proper guidelines so that the "in popular culture" sections/articles aren't (as much of) an embarrassment.
IN POPULAR CULTURE guidelines
the work mentioned must be ABOUT the phenomenon/person/whatever... or, if not actually ABOUT it, the phenomenon/person/whatever must be a sine qua non for the work to exist. Allusions to the name are not enough.
EXAMPLES
the Simpsons episode "A Streetcar Named Marge" *can* be used as an example of "A Streetcar Named Desire" in popular culture. This is because the episode is all about doing a musical production of Streetcar -- and at several instances throughout the episode, the writers drew parallels between Streetcar and Springfield.
On the other hand, the existence, in that exact same Simpsons episode, of the "Ayn Rand Daycare" (where there's an "A is A" sign on the wall, and the director reads 'The Fountainhead Diet'), cannot be used as an example of Ayn Rand in popular culture. Because that's only a tiny fragment of the joke.
One installment of "Bob the Angry Flower" was about "Atlas Shrugged 2: one hour later", but this cannot be used as an example of Ayn Rand in popular culture either. Because even though this was the whole premise of the joke... it was only in one installment of the strip. Considered as a whole, "Bob the Angry Flower" is not about Ayn Rand. Although The Simpsons as a whole is not about "A Streetcar Named Desire", we do have articles on individual episodes of the Simpsons, whereas we do not have articles on individual installments of "Bob the Angry Flower".
On the other hand, Matt Ruff's novel "Sewer Gas Electric", in which one of the main characters is (either the soul of Ayn Rand, or an AI that thinks it is Ayn Rand), can be used as an example of Ayn Rand in popular culture. Later in that same novel, there's a brief appearance of Queen Elizabeth II, but she is not a main character, and thus this is not an example of Elizabeth Windsor in Popular Culture.
Compare Copenhagen as an example of the Uncertainty Principle in pop culture... vs an offhand mention in an episode of Aqua Teen Hunger Force or Futurama.
ANOTHER POINT: the generic reference (this part should go first, maybe?). The example I'm using here is Veal Orloff, which used to include the fact that it had been part of an episode of The Mary Tyler Moore Show and that it had been mentioned on an episode of Frasier. But in neither of those instances did it actually matter that it had been Veal Orloff. As per my edit summary, in both those instances "it could have been MacGuffin Casserole". Compare to the Ayn Rand Daycare in the Simpsons episode, where it had to be Ayn Rand for the series of jokes to work.
YET ANOTHER POINT: the X should only ever be a proper noun. Things represented by common nouns are part of our shared culture; they are generic. Things represented by proper nouns have some specific identity, which can form the basis for an allusion. "Soap in popular culture", "fences in popular culture", "nail clippers in popular culture"... all of these are totally unacceptable. I know we have Category:In Popular Culture, and it needs to be severely trimmed and reorganized.
CAMEOS AND HOMAGES: If (character Y) is an obvious homage to (character X), should that be included? If we have a separate article on (character Y), then the answer is clearly yes. Thus, Sherlock Hemlock is to be included in the "popular culture" section of the article on Sherlock Holmes, as is Slylock Fox. Or if it's a notable work which includes Holmes (and/or characters from the Holmes canon) as significant characters - thus, A Study in Emerald, League of Extraordinary Gentlemen, Without a Clue, The Great Mouse Detective, The Adventures of Shirley Holmes, or Ship in a Bottle (TNG episode). Conversely, having a character make a brief allusion to the Doyle canon - saying "the game's afoot!", or "elementary, my dear X" or "once you have eliminated the impossible", for instance - that's not enough, and doesn't get mentioned.
The key word is significant: Holmes had a brief appearance in one issue of Planetary, and one of Asimov's Black Widowers stories was about dissecting Moriarty's "Dynamics of an Asteroid", but in neither case is that really significant allusion to Doyle's mythos.
THERE ARE ALWAYS EXCEPTIONS - our list of songs about Joe DiMaggio should be limited to songs that are actually about him instead of ones that just mention his name, but "Mrs. Robinson" gets included because its offhand allusion became hugely important, to the point that DiMaggio himself commented on it. Nonetheless, you'd better be able to justify it.