VMware Fusion now virtualizes standard builds of Mac OS X 10.5 Leopard and 10.6 Snow Leopard

VMware released the latest dot update to its flagship Mac virtualization product today. The free update, Fusion 4.1, improves Lion full-screen compatibility, graphics performance and startup options; it can be downloaded immediately for all Fusion customers. While those changes are certainly nice, they aren't the big story in this build.

Macworld's Jason Snell has discovered that alongside the acknowledged changes and improvements, a less obvious adjustment has appeared in Fusion 4.1 in the area of virtualizing Mac OS X itself. Unlike previous versions of Fusion (and other virtualization products for the Mac like Parallels and VirtualBox), which included a built-in limiter to prevent users from installing a non-server version of Mac OS X 10.5 or 10.6 in a virtual machine, the new Fusion build simply reminds you to respect Apple's licensing restrictions -- and then lets you go ahead and install vanilla Leopard or Snow Leopard anyway. Up until now, the only versions of 10.5 or 10.6 that were considered 'legal' for virtualization were the pricey Mac OS X Server versions.

This may seem like a small difference, but it's a seismic shift in the Mac OS X virtualization landscape, and one that could have a major impact for specific 'abandonware' applications on the Mac platform. With the ability to virtualize Snow Leopard easily, VMware users can create a virtual machine that retains the Rosetta code translation stack Apple removed in Lion -- giving those people back the ability to run PowerPC applications. Quicken Deluxe is the most prominent app on the PPC roster, but older versions of Adobe's Creative Suite and QuarkXPress are also up for revitalization in a 10.6 VM.

When I spoke to the Fusion product team during the Fusion 4 announcement, they were somewhat coy about the possibilities for virtualizing Rosetta-capable builds of Mac OS X other than the server versions; the decision on licensing was up to Apple, they said, while they would of course continue to explore their options and keep the lines of communication open to Cupertino. I don't know whether this move towards liberalizing the install was done with or without Apple's knowledge and consent, but I'll ask.

In the meantime, if you're still holding off on your Lion upgrade because you've got PowerPC applications that aren't ready (or willing) to make the leap to Intel code, your options just got much more interesting.