Some of my friends remind me that they use emacs already and don't need this one by Microsoft. Others say they use Sublime Text instead.
I used Visual Studio in the late 1990's and got used to the GUI IDE. I did a lot of work in Classic Visual BASIC before the Dotnet era.
I see they are open sourcing the CoreCLR and now Visual Studio Core. I gave the Linux version a quick look over, extracted the zip file to a directory and ran the ./Core program. It loads quick enough, most likely because there isn't much there.
I have to remember that this is the Post-Microsoft era, and Microsoft has to reinvent itself in order to survive. Microsoft knows the Hacker and Startup community uses OSX and Linux, and many have migrated away from Windows. Microsoft knows they like open source projects, so Microsoft open sourced Visual Studio and CoreCLR to have them ported to Linux, *BSD Unix, and Mac OSX.
Why Microsoft never made a version of Visual Studio for Linux or OSX is beyond me. We got Mono for a while, but it was always behind the Windows version. There was DotGNU but I lost track of where they were at.
If anyone is wondering how Microsoft earns money from open source projects, they will always sell books on it and also certification for it. Like Xamarian they can always buy out the company that forks it and makes a better version of it that is cross platform.