You don't have to be Open Source to be used in the industry, even in the future.  You have to have good marketing, a secure product, and developers willing to develop for the platform, whatever the platform is.  If you think Open Source will be the only form of development in the future, your dead wrong.  It will be a mix of Corporate (Closed Source) and Open Source.  Both with their advantages/disadvantages.  Licensing is a core issue with both, Open source being a little more complicated.

I don't think them open sourcing changes anything but the marketing perception.  No more than if Microsoft Open Sourced .NET.  So what.. you still won't get different adopters just because it is a Microsoft product.