Well, the soil is radio-active. Everything is charred and melted. I'm not sure that it's meant to be our Earth. If it is, it's quite a statement.
Think about it. These poor people and Cylons wander around the galaxy looking for the lost colony. Finally they find it. Only, it didn't take Cylons (non-humans) to nuke it. We on the lost colony did it to ourselves. It's rather poetic, actually. Humans destroy themselves with their own creations (terminatorish) on the 12 colonies and on the 13 they use weapons of their own creation that the Cylons used to destroy the 12 colonies to destroy their own planet to life.
However, I agree with Hazelgod. Something is going on. It's still mid-season. Perhaps it was a vision someone was having. Perhaps it's an old outpost (a 14th colony, if you will). Could it be Kobol? Is it a Cylon trick? Could it have been a Cylon planet destroyed by their own civil war?
And we still have the unresolved plot of the final revelation of the 5th Cylon. Wasn't that supposed to happen when they find Earth? It didn't happen yet, and from the looks of that planet it ain't happening on that planet, whatever it is.
I hope that "Caprica" is actually a good series and not at all like the first 3 "Star Wars" movies that were made at the beginning of this century. If that's an example of how shoddy prequels can be made then I hope the writers and actors of "Caprica" can avoid the mistakes that Lucas and Co. made in the Star Wars fanchise.