What would happen if Microsoft shutdown?
A company as large as Microsoft would not shutdown overnight. There have been many companies in the technology industry that were pretty large that you probably may not have heard of that still exist in one way or another in companies that exist today.
What do you think of Microsoft joining the Linux Foundation?
I am not shocked or excited. I am actually surprised it didn't happen sooner. Microsoft has been embracing various open source projects in recent months (see links below), so I don't see why the attached article makes it to be such a big surprise.
As Google has shown with Android you can straddle the fence successfully between supporting an open source operating system while still maintaining a fair amount of proprietary components.
http://www.zdnet.com/article/microsoft-loves-freebsd-so-much-it-has-made-its-own-vm-image-for-azure/
http://www.zdnet.com/article/microsoft-pushes-more-open-source-with-net-engine-coreclr/
Steve Jobs meets Steve Ballmer
Ballmer: Saving Apple in 1997 was 'craziest thing' Microsoft ever did http://www.cultofmac.com/393889/ballmer-saving-apple-in-1997-was-craziest-thing-microsoft-ever-did/
If Only Steve Jobs Were Alive To Witness The Final Destruction Of Microsoft https://techpinions.com/if-only-steve-jobs-were-alive-to-witness-the-final-destruction-of-microsoft/22121
Steve Ballmer's Biggest Mistakes As CEO Of Microsoft http://www.businessinsider.com/steve-ballmers-most-epic-mistakes-as-ceo-of-microsoft-2013-8
Five crazy things Steve Ballmer has done http://fortune.com/2014/05/31/steve-ballmer-crazy/
Former Microsoft CEO Steve Ballmer calls 1997 investment saving Apple “craziest thing we ever did” https://9to5mac.com/2015/10/23/former-microsoft-ceo-steve-ballmer-calls-1997-investment-saving-apple-craziest-thing-we-ever-did/