IGN quote from urk

by thesirchelios , Sweden, Monday, June 03, 2013, 17:36 (4189 days ago) @ Xenos

I don't think it has as much to do with Bungie as it does with Activision and their deals with Sony and MS. They are after all the publishers of Destiny and probably in charge of most of the marketing, and seeing as they already have CoD on Xbox, why not get the best of both worlds and promote Destiny on the PS? That way they have their two big franchises on two different platforms, in terms of what they will be associated with by the average consumer. People like us who follow Bungie and Destiny rather closely know that Destiny will be awesome on which ever platform we chose to play it on, but the average consumer or average gamer are going to more closely relate Destiny to the Playstation the way they do CoD to the Xbox.
There is also the fact that they need to work a bit harder to bring in the Playstation audience, who do not necessarily know a lot about Bungie and how awesome they are, whilst they already have a big following on the Xbox. It's like if Naughty Dog separated from Sony and made a multiplatform title, they would probably market it more heavily towards the Xbox audience who would not be as familiar with them. (On a side note, man I want to play The Last of Us!)
Thirdly like you said is that MS want to show off exclusive content, and bringing in Bungie who was their golden boy in years past would send some weird mixed signals about the state of their own studios! It is one thing to show off CoD, which is an established franchise that has had Xbox exclusives for a while now, Destiny is brand new and doesn't have the same punch yet.