I did love both episodes. I liked the subtle reference to Alan Scott in "Steam Lantern" and I'm glad they at least used a different Earth in their arc with the Anti-Monitor. I doubt we'll see a full-fledged "Crisis" storyline, which is fine, but it was a nice nod, nonetheless.
I don't think they ever said it was a version of Earth. I was figuring it was more like one of those cartoon/comics/'60s-SFTV alien worlds that just coincidentally happen to duplicate a historical Earth culture or a variation thereon.