Anyone who's worked in the IT field is familiar with Microsoft applications. For years Microsoft ran many offices, through their desktop software, networking applications, firewalls, mail servers (microsoft exchange) and on and on the list goes.
Open Source has always existed, ever since Wozniak wrote the first operating system and started to share it on the Apple I. But I think that for the longest time most people in IT were afraid of Open Source - and there were some good reasons. People felt that an open platform meant you were more likely to get hacked and viruses - if everyone can see an application's vulnerabilities, anyone can get in - right?
Well now, Open Source Software is taking over, in a big way. IT managers and those in decision making positions are realizing (through much education by open source advocates) that this type of development actually makes applications more secure, because more peer review by developers fixed more bugs, and white-hat hackers supplied their knowledge to vulnerabilities.
Now we're beginning to see open source running some of the most complex and corporate infrastructures in the business information field to-date. Big systems such as Cloud Linux, and android are using Open Source technologies
Open Source is becoming the lynch pin to business technologies. Cloud computing will use Open Source, Analytical Systems will too. Open Source is currently poised to become the premiere and preferred platform for building information systems. Even Microsoft has added Enterprise Data system Hadoop to it's cloud application Azure.
Open source isn't just a technology, it's a way of life to developers and IT professionals, and I can only see it continuing to take over the proprietary space as more and more of these applications and developers are empowered to be able to write code to help applications talk to each other.