Slate's Jody Rosen has a nice article here. The long and the short of it is that while the individual elements of the dance can be isolated, it's true genius is its whimsical retro feel: it's one part vintage late-80s hip-hop (think Kid N' Play meets Rob Base), one part early-century jazz-dancing, and one part pure silliness, the body language of small kids and old people after dinner at a wedding. In short, it's the sort of thing that, twenty years ago, I totally would have been practicing in a mirror after my sister taught me how to do it.
Thoughtful quote from the Slate article:
Whatever repercussions the rise of online video has for music and the music business, it's doing wonders for dancers. One can't help but suspect that we are entering a new dance craze golden age, in which the emphasis will be laid firmly on the dancing in dance music. Regional steps and styles, zapped across the world via the internet, will compete for global predominance.