[72deluxe]

The HFS+ problems would not be related to VirtualBox. VirtualBox gets a bad press from the Linux kernel mods too.

Apple introduced a new virtualisation framework in Yosemite, hence the rereleases of the most widely used virtualization items (Parallels and Fusion).

[rab_oof]

Sounds post hoc. The virtualization products tend to be on regular, frequent release cycles. (I know one of the Fusion product manager.)