VirtualBox v4.0.0 Beta 1 is released. VirtualBox is a general-purpose full virtualizer for x86 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.

VirtualBox v4.0.0 Beta 1 Changelog:
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

Download: VirtualBox v4.0.0 Beta 1
Source: Here