Well if Girl Genius doesn't count as Steampunk, then certainly Court of the Air certainly wouldn't since that has actual magic as the basis for the "technology". But I would actually consider both of them, and Laputa as well to be steampunk, in that they all have the trappings of pre-electronic era technology and are heavily informed by the pulps. Certainly Girl Genius is as much a satire on the pulps (as the early appearance of the Heterodyne Boys showed), but it still has the neo-Victorian trappings.

Really, Steampunk is Alternate History as much as it is fantasy, so I feel OK with being inclusive as far as works go. By doing such, there also extends the hope of sometime in the future making the genre more inclusive as well.