Destiny is going to be one of those titles that straddles generations, but that doesn't mean it'll be gimped on the older intended platforms.
Obviously, those playing it on the PlayStation 4 (and perhaps the Xbox 720, as the game is expected to be confirmed for that platform as well), will receive better graphics than those who experience it on the PS3 or Xbox 360. But as developer Bungie told their fans , those who don't immediately upgrade to the next generation of hardware don't have to worry:
"We’ve been planning for multiple hardware platforms from the very beginning, and while we can’t get into the minute technical details of each console, we’re fully committed to delivering our full vision for Destiny on every console we ship on. Currently, that list is PlayStation 4, PlayStation 3, and Xbox 360."
Known as a "shared world shooter," Destiny is a hugely ambitious project, although sometimes we wonder how many PlayStation fans will be interested. Remember, Bungie spent all of last generation making Halo titles for Microsoft, so this is kinda like Final Fantasy going multiplatform last generation. …okay, maybe it's not exactly the same, but you get my point.
Related Game(s): Destiny