The Mephisto Waltzes seem to me to be country dances that evolve into orgiastic tone poems, all based on the program supplied by Juufa. Liszt was clearly obsessed with this program as he set it four times, and there is also a Mephisto Polka! Never heard that, though. There's this idea of the worldly sophisticated travelers barging in on a bunch of hicks partying, and they transform the happening into one of their own fashion, using music as the supernatural aphrodisiac. Who says Victorian times were prudish?
I think Liszt is using the idea of the Waltz, THE dance of the 19th Century, as a metaphor for sex. The Valses Oubliees (late pieces) are perhaps the old man remembering episodes from his youth. At any rate these are stylized waltzes, not waltzes a la Strauss, Schubert or even Chopin.The waltz is now a symbol for you know what.
That's just my random opinion, though.
As for the poll, no, in terms of what a waltz actually is; a dance piece. These are something else entirely.