Alright party penguins. We are proud to announce the launch of Civ VI Linux today (Feb 9th)!
I'll keep this thread updated with the most current info possible, so check in frequently for updates and of course to share your experience.
A huge heartfelt thanks to all the patient Linux gamers that supported our efforts. Especially those that sent cookies to our office with notes of Civ VI encouragement ;)
System requirements below:
Operating System: Ubuntu 16.04 / SteamOS
CPU Processor: Intel Core i3 530 or AMD A8-3870
CPU Speed: 2.93 GHz
Memory: 6 GB
Hard Disk Space: 15 GB
Video Card (NVIDIA): GeForce 650
Video Card (ATI): Not Supported
Video Card (Intel): Not Supported
Video Memory (VRam): 1 GB
IMPORTANT NOTICE: Some Intel i3 Processors may require an additional 2 GB Swap Partition.
If you dont meet the above system requirements, that does NOT mean you wont be able to run Civilization VI. If we know anything about the Linux community, its that you all find a way to make something work on your specific distro and comparable hardware sets. Chime in here with issues, and we will either help you get a ticket into our support system, or if unsupported there are many penguins that can help.
UPDATE 3/14/17 - We are live with Australian Summer! Linux and Mac are still in sync. Full details from the Windows announcement: http://steamcommunity.com/games/289070/announcements/detail/576861888092920827
UPDATE 4/20/17 - We are finally live with the Spring update!
UPDATE 12/10/18 - Cross platform update is finally live! All platforms are now in-sync and can play together.
UPDATE 4/2/19 - The Antarctic Late Summer Update is now live. All platforms in-sync and can continue cross platform play :)
UPDATE 9/10/19 - September 2019 update is now live! All platforms in-sync and can continue cross platform play. Enjoy Red Death!

Forward for Freedom!
Maybe if Take-Two bought Aspyr
Its going through QA approvals as I type. I should note that QA sweeps on a game this large is no small task...but we are talking a matter of weeks, not months.
I'm sure someone will make a mod for that sooner or later.