None…

Wikipedia defines a “meme” as consisting “of any unit of cultural information, such as a practice or idea, that gets transmitted verbally or by repeated action from one mind to another. Examples include thoughts, ideas, theories, practices, habits, songs, dances and moods and terms such as race, culture, and ethnicity.” An internet meme, similarly would be “a catchphrase or concept that spreads in a faddish way from person to person via the Internet.” (Though sometimes the term internet meme is “is used loosely to refer to things that are not necessarily memes in a technical sense.”) They also claim Hampster Dance was the first widely distributed internet meme. Hampster Dance had music, but not really words.

Secondly, despite the name, and the fact that many participants do not use words in their posts (thus leading to this Tell Me Thursday meme), words are not strictly verboten when playing Wordless Wednesday. As the site says, “there are no rules!” (Interestingly enough, WW is not strictly Wednesdays anymore, either. It’s now a daily meme.)

I would say that Tell Me Thursday is definitely also a meme, and a pretty cool one at that. I bet a lot of people are interested in hearing the stories behind the photos.