To quote INSANEdrive's post... (Destiny)

by Xenos , Shores of Time, Saturday, July 05, 2014, 12:40 (3804 days ago) @ UnrealCh13f

360/One requires a Gold account to play any of the game.

Not true according to Phil Spencer:

...Destiny is a great example of a next gen game experience that I think maybe we will see more of. A game that blends a single player story driven campaign with online spaces where you will see other players, [...and ya know while...] thinking of next gen games one of the things I want to make clear to people in these single player experiences where you see other people in story driven mode, those will obviously be on Xbox live. Those aren't Gold features, those will be features that people can use if they are free member of xbox live. Now obviously PvP, Co-Op ... the stuff that fully uses xbox live is still gold.