Not trying to defend Crystal Dynamics' decision as I was hoping I would play the game on my PS4, but I can kinda see why they went this way.
From what it looked like, Rise of the Tomb Raider and Uncharted 4 were coming out at the same time and, naturally, Sony's going to promote Uncharted 4 over Tomb Raider. In a move that makes sense for CD, they align with Microsoft and have them promote it against Uncharted as competition and as a Xbox One exclusive.
The thing that irks me is that because of this Xbox One exclusivity is that PC owners will have to wait for this game to release as well. Maybe Microsoft learned their lesson from releasing Titanfall on 360 and PC? Who knows.
The better question is this: How many of us here, who're currently complaining about the game's exclusivity, will cave and get a Xbox One the closer we get to launch day. I know that all of us right now are pretty upset about the news, but these feelings don't last forever.