It's where the industry is heading.
Both console manufacturers are going to throw money at publishers and dev companies in order to get timed-exclusivity to try to get a leg up on their competition.
We saw this with Skyrim when Microsoft reached into its very deep pockets and got that timed-exclusivity for all of Skyrim's DLC, even over the PC crowd. Destiny is just another skirmish in that war, and the Destiny battle goes to Sony for the timed-exclusives with Destiny.
But we see this with many multiplat franchises, and we'll see more. I can guarantee that.
As long as we as Gamers continue to throw our money at this industry, they'll continue to wage this back-and-forth battle on a nigh infinite scale.