Aethulred:
OK, That explains the lack of an RTJ or anything else normally found in a game link... Thanks.
One of the things for Steampunk is the "Grandeur" and newness of things encountered. Examples are numerous:
Climbing up a mountain to discover a plateau of dinosaurs
Crashing into a mountain to discover a secret city
A new military concept based on the new thing... radio... machine gun... flying.
Attending a gala ball with royalty, monarchs and ministers of nations nearly at war
These things also tend to present that what the character (novel or game) do will affect the future of the world.
Steampunk, and Victoriana, also let us challenge the ideas of the "what if" had been slightly different. A technology we take for granted today would be wonderous if a steam punk version existed. How does that change the world? Often only one side/power has the new thing. Sometimes more.
If you include air or space travel in the setting then you have a huge expanse of exploring. Places we might know today are found earlier. Resources, like say gasoline or uranium, become politically important while most are still on whale oil lamps or coal for their ships.
The "what if" is something that turns history into steampunk.