VirtualBox 3.1 with Improved Management.

Although VirtualBox 3.1 is designated a minor release, the changelog shows some important updates in snapshot management apart from numerous bugfixes. The new release also allows migrating a live VM session from host to host.

Sun has been satisfying what looks to be the steady growth of users with almost monthly versions of VirtualBox. Whereas the changes to the last major release 3.0 update were less than spectacular, the current version provides some important and for users quite sensible new features. The snapshot function saw some especially fundamental revisions. Any previous snapshot can now be restored to be the current VM state and new snapshots can be branched from existing ones.

Live migration is a new feature, called teleportation, in VirtualBox that is based more on business requirements. It allows porting a VM session on a running basis from host to host.
Sun also reports a performance improvement for PAE and AMD64 guests in the changelog. Network performance underwent some changes as well. It's now possible to adjust network settings for the VM while it's running and the implemented NAT can act as a DNS proxy.

The free VirtualBox software under a personal use and evaluation license is available for download as packages for Linux distros in addition to Windows and Mac OS X. Sun also provides the source code for VirtualBox OSE, the open source edition under GPLv2 license.