Microsoft announced the availability of the first public release candidate for SQL Server 2019 several hours ago!
SQL Server 2019 is a cross platforms application which is supported on all common operating system directly and/or using containers. It provide multiple new and upgrade features like Big Data Clusters, Data virtualization with PolyBase, execution of custom Java code along the same lines it executed R and Python, Support UTF-8 character, Enhancements to intelligent query processing, Automatic tuning and Improve database availability, and more
You can download the application from Microsoft's Evaluation Center with free licence for 180 days.
So why should you download and install it now?
"Release candidate" (RC) means that the software is feature-complete, or in other words all features are in but you might still encounter some bugs. I always treat "Release candidate" as a final beta for testing and it should never be used for production. The RC stage implies that the RTM and commercial product releases are coming soon.
Important links to get more information