I stumbled upon this while reading OPM UK's "Studios that are doing the PS4 right" online article. The article states, "Destiny’s take on multiplayer starts with co-op, with two players playing splitscreen, but also throws in ‘Public Areas’ – pre-defined points in the game where other bands of players can join up together to take on specific challenges, like bringing down a particularly bothersome alien." I'm not sure if this is a mistake, but Rich Wordsworth specifically mentions "two players playing splitscreen". I know there are bits and pieces of information hinting at local co-op, but it seems that there's nothing really concrete. I hope it's true.