I'm getting a little annoyed with the whole concept of "our earth." Who cares?
Stargate takes place on "our earth," but neither Bill Clinton nor George Bush were ever the President.
Angel took place on "our earth," but I don't remember a giant demon completely blotting out the sun a few years ago.
BSG's Earth could very well be "our earth" in much the same way, but in the context of the story, it really doesn't matter. The Fleet found Earth. Not our Earth. Not a fake Earth. Just Earth.