Seems to be getting lost in the hubbub:

http://news.xbox.com/2014/08/gamescom-xbox-one-gamescom-press-release

• “Rise of the Tomb Raider” (Crystal Dynamics, Microsoft Studios). In her first adventure, Lara Croft was forged into a true survivor, but she glimpsed a deeper, secret world. In the next chapter of her journey, Lara must use her survival skills and wits, learn to trust new friends, and ultimately accept her destiny as the Tomb Raider. Launching in holiday 2015, exclusively on Xbox, featuring epic, high-octane action moments, “Rise of the Tomb Raider” will take gamers to multiple locations around the world filled with exploration spaces that are some of the most beautifully hostile places on earth. In addition, after hearing the cry from fans loud and clear, the game will put the tombs back into “Tomb Raider,” all in the franchise’s gritty Survival-Action style.

I know a lot of games tend to go timed exclusive when this sort of thing happens, but they are not typically published by a first party...

Edit: Geoff Keighley saying listing is an error! This news story, changing by the minute. Stay tuned!

Edit 2: Greenberg tells Keighly off, still doesn't definitely state game never going elsewhere.

Edit 3: Microsoft removed as publisher listing. Some viewing Greenberg's post as confirmation of exclusivity - others viewing ambiguity as proof of timed exclusivity.

Thread/

This is awkward...
Geoff Keighley @geoffkeighley 1m
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Trying to get more clarity on Tomb Raider. Xbox tells me Microsoft Studios is not publishing game and listing on web is an error.

Not publisher, but picked last option anyways.

yep ill just drink something strong.

MS was the publisher of Ryse as well....
And so was Dead Rising 3.....
And so was Minecraft for the 360.....

They've published games in the past that eventually go to other platforms anyways. And it is full out exclusives then kudos to SE for killing their franchise.

So timed exclusive confirmed?

okay so its a 6 month times exclusiv

This news story is insane! The news changes every two minutes!