Personally, I'd like to take things a bit further, mostly because the one thing I see in the scene, the one thing that constantly pisses me off, is this dependence on Victorian aesthetics, or worse, people denigrating something simply because it isn't Victorian enough to be Steampunk.
These kind of things boggle the hell out of me. Partly because I came to the aesthetic from fiction, including works that don't have a thing to do with Victoriana, as well as comics and videogames that, while steampunk, also didn't have a goddamned thing to do with anything Victorian.
Honestly, for me, the Victorian era and Steampunk are about as congruent as a fish and a pickup truck, respectively.
Sure, you can carry a fish around in your truck, should you desire it. But the fish does not normally, or necessarily belong inside of said truck. And the truck does it's own purpose just fine, regardless of whether or not there's a fish in the back end. Neither one requires the other, and, in fact, they can both exist separate of each other just fine.
It's the same with Steampunk. Most definitions of it start talking about how Steampunk had its roots in Victorian Science Fiction, and then utterly fail to realize that that's not the end of things- that about the only thing that really defines steampunk as a literary genre is high adventure, wild unknown factors, and steam-driven technology. Note the lack of fashion references in that list? That's because there aren't any. Characters in Verne's novels were dressed in a victorian manner because he was writing contemporary novels- had Verne been doing the same writing in our own time, his characters might have just as easily been wearing t-shirts and jeans. Would the book still be considerable as Steampunk lit? Absolutely, provided it had the other elements of the genre.
So, to the costume nazis desperate to see everyone in corsetry, waistcoats and such? Stow it. Their choices in costuming and everything are just as valid as yours.
And let's face it. Over a long enough time, a truck simply needs more fuel added to it to keep it going. Whereas a fish will only develop a rather bad smell, and need to get thrown over for a fresher fish.
And for the record, there's no way in hell you're going to catch me defining steampunk any further than this. It's a growing genre/subculture and is still finding it's own definition, which isn't helped by everyone trying to slap labels on it to justify their own choices. Leave it for the historians to do in a century, if it makes it that far.