Spoilers are precisely defined here. Rules vary by the story's medium. Info from television stories can't be added here until after the top or bottom of the hour, British time, closest to the end credits roll on BBC One. Therefore, fans in the Americas who are sensitive to spoilers should avoid Tardis on Sundays until they've seen the episode.
Although Pluto was downgraded from full planet to "dwarf planet" in 2006, numerous stories produced prior to this date and set in Earth's future identify Pluto as a planet and Charon as its moon, suggesting that, in the Doctor Who universe at least, Pluto's planetary status was eventually restored.