Obviously, for better or for worse, some folks just go with "Add goggles & gears and call it good to go" (which really ought to be a meme-style summary-catchphrase in the Steampunk community). Myself though, I have a definition that stems more from the cyberpunk roots in the Speculative Fiction department (IE: from William Gibson to Paul Di Filippo's Steampunk Trilogy and Tim Powers and all).
Ok, so I've generally understood the idea of CyberPunk as stories set in a future where some select narrow fields of technology have advanced faster than others, and where the culture hasn't quite caught up to that level of technology, leading to stories focused around disenfranchised folks in that setting (that'd be the 'punk' part), or leading to stories focused around the general dystopia where everyone is disenfranchised. Obviously, this generally goes with a more recreational sort of technology (like the stories where folks are addicted to virtual reality), and/or with technology of convenience (an example would be that episode of Max Headroom where our hero's credit/ID cards were canceled, or the Tuttle/Buttle confusion in the film Brazil), and the dystopian aspect is how folks haven't quite learned how to adapt to the technology (and you know, the legislative aspects of the Anita Blake books' setting could be seen as a sort of MagicPunk if one wrote stories hinging on the particular focus of how there's some really poorly constructed preternatural legislation).
I'd guess that such a split could come up from extra-new tech that cropped up before folks could learn about it to teach their kids. You know? It seems that for a thing to be ingrained into society, you need to have the kids who are being raised on/around Thing X to have parents who were also familiar with Thing X as kids. I could see current real-world examples of that being the need for laws disallowing text-messaging while driving, or the whole 'netiquette' thing (since today's kids are being raised by folks who were, at best, kicking around BBS systems on their C-64s).
Anyway! Moving on! I see SteamPunk as a setting as being a similar thing to the CyberPunk setting, but set in an alternate dystopian past. A timeline where the Victorian world happened to have a few narrow-range leaps in technology, so you've clockwork horses and suchlike, but since the entire society didn't advance (since the parents didn't grow up with it so the next generation ran carte blanc) you still have shoeless orphans getting roped into coal-mining with those clockwork horses.
Alas, that doesn't help with the person's original query since by my yardstick, belly-dancing clothes would most likely be exactly the same (since, well...they're based on a style that is currently used and was used quite some time pre-Victorian, and I can't see a few tech-leaps really changing that, unless it's more easily constructed cloth or automaton dancers).
And speaking of convenience-tech, I was pleased to discover that one doesn't have to make an account at Last.FM to be able to listen to someone's library there! Which means...(drumroll)...anyone online with speakers can dial up my Last.FM profile and listen to a randomized selection of my bad music! Woo hoo!