No Such Thing As Alien Pop Culture: Averted, for the most part – even without the dodge, I suppose, of pointing out that the Imperials would consider our distinction between high culture and low culture the product of a certain type of class-based social structure that humans have, and sniff rather loudly at the parochialism that assumes that primate status bigotry (with signifiers everywhere!) is a universal species trait.
I shall instead merely note those things of which the canon has named examples at this point, including music (all the forms listed under Future Music can be considered popular, except the most gratuitously complicated forms of opera and metatonal), an extensive literary culture that includes popular novels (speculative fiction is the Genre That Ate The Mainstream, which in turn becomes the subgenre referred to as “realist fiction”), epic poetry (even in the modern day), graphic novels, watchvids (i.e., non-interactive movies and television), InVids, slinkies, virtual-reality games, virtual-reality cosmoi, alternate-reality games, regular computer games, RPGs, board games, mechanical toys, recreational dueling and non-combat challenges, haut cuisine, participatory (although much less so spectator) sports and, yes, even spam.