Seraphim vault, jovian complex, kings watch are accessible since alpha and beta. Not the legit way, but people have been glitching into these areas during the alpha and beta of this game. They were accessible since destiny's launch in the full game. The area with the second strike on ps is accessible since launch of retail version, it was probably there during the beta but since that was limited to earth not way for anyone to enter it. Kings watch even has enemies with the mini boss, had them in alpha and beta and still has them. Guess what it will be unlocked to us with house of wolves dlc in march 2015 as a new dlc. Other area's on venus and mars are also accessible since the launch of the game. Some of those area's even have dead ghosts which can be picked up mate.