Received an email from VirtualBox Team informing release of new beta version VirtualBox. Please do not use this beta version for your production environment. A VirtualBox Beta release should be considered a bleeding-edge release meant for early evaluation and testing purposes. 

You can download the binaries here:   http://download.virtualbox.org/virtualbox/6.0.0_BETA2

Version 6.0 will be a new major release. Please see the forum at https://forums.virtualbox.org/viewtopic.php?f=15&t=90315 for an incomplete list of changes.