The teen plastic surgery trend—what trend? Westerfeld's main characters may be teens getting some pretty radical plastic surgery. But according to the American Society for Aesthetic Plastic Surgery, rates of teenage plastic surgery have been pretty flat. So remember that the next time your local news breathlessly reports about some dangerous trend of teenage plastic surgery. (And to be fair to Westerfeld, he notes in an interview that one of his inspirations for the book was adult plastic surgery. (source) and (source)
Bogus? Bubbly? Hovery? Uglies sure has a lot of slang. Westerfeld notes that he really likes slang and he takes it from wherever he wants, like Australian slang ("littlies") and Evelyn Waugh's 1930s book Vile Bodies ("bogus" and "bubbly"). That's probably why Westerfeld went ahead and wrote a guide to this series, including a slang section. (source)
In Uglies, people get surgery so they all look pretty, but a few other stories include some radical plastic surgery to make everyone equal. L. P. Hartley wrote a book in 1960 titled (awesomely) Facial Justice, where people get surgery to look plainer. And the classic Twilight Zone episode "Number 12 Looks Just Like You" (1964).
Hoverboards. Everyone loves them, even people in the 1960s, which is why Popular Mechanics put together this photo spread on hovercraft technology. (Unfortunately, skateboards weren't a thing back then, so these "hoverboards" are mostly big, car-like vehicles.) (source)