I was also disappointed at first by the Earth news, it also made me doubt the reliability of CongoRed as it seemed unlikely.
However, the theory about "old-Earth", "new-Earth" like "Caprica" and "New caprica", that has been suggested by some on scifi, may have merit. In this case, the roadsigns really all were leading to Earth - only, it wasn't "our" Earth. That will be the planet the survivors fled to, and in time the "new" will fall off the name, I guess. And the with the help of the final Cylon, the colonials will find it, and Roslin will die before she ever makes it there. It is consistent with foreshadowing, that way, and some of the comments from writers like "what they call Earth, anyway" also point in that direction.
I think it could work.