On TV and film, the nomenclature for planets is always based on the star and how many planets the planet is away from that star, i.e. Rigel 7, or Omicron Persei 8. So Earth would be, to a Rigellian, Sol 3. And now you know.
Apart from that, I can’t say anything more than Phil Plait on the newly discovered potentially Earth-like planet, so I’ll just link to his blog entry [link]