Due to the recent announcement of the next Tomb Raider installment being exclusive to Xbox One, Geoff Keighly took it upon himself to ask multiple Microsoft employees about it at Gamescom. According to him, they've told him it's only exclusive for one Holiday season.
Aaron Greenberg, the head of Marketing at Microsoft, claims otherwise, but who is telling the truth?
I actually believe it's a timed exclusive, as I already made that guess yesterday. What helps here is that other Xbox One exclusives such as Plants vs Zombies: Garden Warfare, Dead Rising 3, and Ryse: Son of Rome are now making their way to PlayStation 4.
This is why I didn't complain about it at all. Microsoft sucks at keeping 3rd party exclusives.
Source: http://www.gamnesia.com/news/report-rise-of-the-tomb-raider-is-a-timed-exclusive-microsoft-denies#.U-uN0sEpDQ8
EDIT: Phil Spencer confirmed the timed exclusive in an interview with Eurogamer.
Source: http://www.gamnesia.com/news/xbox-boss-confirms-rise-of-the-tomb-raider-is-a-timed-exclusive#.U-uRv8EpDQ8