Please do NOT use this VirtualBox Beta release on production machines. A VirtualBox Beta release should be considered a bleeding-edge release meant for early evaluation and testing purposes.

You can download the binaries here.

Please do NOT open bug reports at http://www.virtualbox.org/wiki/Bugtracker but use our VirtualBox Beta Feedback forum to report any problems with the Beta. Please concentrate on reporting regressions since VirtualBox 3.2.12.

Note: As of version 4.0, certain features of VirtualBox are shipped as part of external packages (extpacks). There is currently one extpack available: The PUEL extpack adds support for USB 2.0, RDP server and the PXE bootloader with E1000 support. To install this package, open the VirtualBox Global Settings and open the Extensions pane.

Version 4.0.0 will be new major release. The following major new features were added:
New settings/disk file layout for VM portability; see the manual for more information.
Open Virtualization Format Archive (OVA) support; see the manual for more information.
VMM: support more than 1.5/2 GB guest RAM on 32-bit hosts
Language bindings: uniform Java bindings for both local (COM/XPCOM) and remote (SOAP) invocation APIs
Chipset: added support for the Intel ICH9 chipset with 3 PCI buses, PCI express and Message Signaled Interrupts (MSI)
Audio: Intel HD Audio is now available as guest hardware, for better support with modern guest operating systems (e.g. 64-bit Windows; bug #2785).
GUI: redesigned user interface with guest window preview
GUI: new display mode with downscaled guest display
Resource control: added support for limiting a VM´s CPU time and IO bandwidth.
Storage: support asynchronous I/O for iSCSI, VMDK, VHD and Parallels images
Storage: support for resizing VDI and VHD images
Windows Additions: support for automatically updating the Guest Additions (requires installed Windows Guest Additions 4.0 or later)
Guest Additions: support for copying files into the guest file system
In addition, the following items were fixed and/or added:
VMM: Enable large page support by default on 64-bit hosts (applies to nested paging only)
VMM: fixed guru meditation when running Minix (VT-x only; bug #6557)
GUI: the guest VM list is now sortable
GUI: add the possibility to delete all harddisk attached to an VM, when this VM is deleted (bug #5511)
GUI: built-in creation of desktop file shortcuts to start VMs on double click (bug #2322)
GUI: add configuration dialog for port forwarding in NAT mode (bug #1657)
GUI: show the guest window content on save and restore
GUI: certain GUI warnings don´t stop the VM output anymore
Settings: deleting a machine now automatically deletes all snapshots and saved states as well, it is no longer necessary to manually delete snapshots first; VBoxManage unregistervm --delete can do the same now
Snapshots: added screenshots
3D support: allow use of CR_SYSTEM_GL_PATH again (bug #6864)
3D support: fixed various clipping/visibility issues (bugs #5659, #5794, #5848, #6018, #6187, #6570)
3D support: guest application stack corruption when using glGetVertexAttrib[ifd]v (bug #7395)
2D Video acceleration: multimonitor support
VRDP: fixed rare crash in multimonitor configuration
Display: fixed occasional guest resize crash
NAT: port forwarding rules can be applied at runtime
SATA: allow to attach CD/DVD-ROM drives including passthrough (bug #7058)
Floppy: support readonly image files, taking this as the criteria for making the medium readonly (bug #5651)
Audio: the DirectSound backend now allows VMs to be audible when another DirectSound application is active, including another VM (bug #5578)
EFI: support for SATA disks and CDROMs
BIOS: reduce the stack usage of the VESA BIOS function #4F01 (Quake fix)
OVF/OVA: significant performance improvements during export and import
OVF/OVA: creation of the manifest file on export is optional now
OVF/OVA: allow overwriting the target disk format on import
OVF/OVA: fixed export of VMs with iSCSI disks
Storage: Apple DMG image support for the virtual CD/DVD (bug #6760)
Linux host USB support: introduced a less invasive way of accessing raw USB devices (bugs #1093, #5345, #7759)
Guest Additions: Shared Folders now can be marked as being auto-mounted on Windows, Linux and Solaris guests
Linux Additions: Shared Folders now support symbolic links (bug #818)
Linux Additions: combined 32-bit and 64-bit additions into one file
Windows Additions: automatic logon on Windows Vista/Windows 7 is now able to handle renamed user accounts; added various bugfixes