The open source edition of VirtualBox is GPLv2-licensed, while the full binary versions of VirtualBox are under a "Personal Use and Evaluation License," which precludes deployment in a business scenario. VMware Player, on the other hand, is closed source through and through. Although it's free for personal noncommercial use, it must be formally licensed in a commercial setting. (Player is also not supported by VMware, except when purchasing a license for VMware Fusion Professional.)
VirtualBox also has full implementations of a few features that VMware Player has in more limited incarnations, including snapshotting, virtual-network management, and cloning of workstations. There are some VMware-only functions, such as upload/download to vSphere, implemented in VMware Workstation only, but not in either VirtualBox or VMware Player.
For those willing to put their money down, VMware Workstation is the easy winner. It isn't just the performance, but the polish and the cross-integration with other VMware products that make Workstation worth the money. That said, VirtualBox is no slouch, and it has a few useful items that aren't available in either Workstation or VMware Player.
If you have the cash to spend, VMware is the easy choice. If you're on a tight budget or need a product with liberal licensing, go with VirtualBox.
This story, "Review: VMware Workstation 9 vs. VirtualBox 4.2," was originally published at InfoWorld.com. Keep up on the latest developments in virtualization at InfoWorld.com. For the latest business technology news, follow InfoWorld.com on Twitter.
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