Windows 7 Adds Virtualized XP as Option

Microsoft revealed that Windows 7 would offer an optional, downloadable Windows XP virtual machine today to provide full backwards compatibility. Veteran Windows watchers Rafael Rivera and Paul Thurrott of SuperSite for Windows were given the nod to release the secret.
##CONTINUE##
The Windows XP Mode won't ship with Windows 7, but will be available as a free download for Professional, Enterprise, and Ultimate system owners. The XP mode will comprise a Virtual PC 7 virtual machine and a fully licensed copy of Windows XP Service Pack 3. While this might weigh in at a couple of gigabytes, that's no longer an onerous one-time download even for most home users. (I have to download nearly a gigabyte of Leopard updates if I install 10.5.0 on a fresh machine.)

Windows XP Mode will be a separate environment, but allow running programs to appear alongside Windows 7 programs, rather than locking them inside a window - this sounds just like the Coherence mode that I believe Parallels was the first firm to offer for Windows running under Mac OS X (Intel). (See "Parallels Desktop Ups the Ante," 2006-12-04.)

The strategy is clear. Including XP in a virtual machine allows XP users to make an immediate leap to Windows 7, buying new hardware that will run XP far faster, while preserving a functionally identical operating environment (one that's likely to be more stable and portable, too). Microsoft can break all the compatibility it wants with Windows XP (and perhaps Vista, too) in Windows 7, jettisoning old code, programming hooks, and other detritus.

Last year, I wondered why Microsoft hadn't simply coupled its Virtual PC division with XP for the release of Vista in "Microsoft Needs to Empty Windows Trash, Reboot" (2008-06-29) when I recounted how many times Apple repackaged compatibility layers and virtual machines when it cast off successive older operating systems or architectures. Apparently, I wasn't alone in asking that question.

This is a fairly brilliant move for Microsoft, and somewhat out of keeping with a company that has made backwards compatibility, sometimes stretching decades into the past, one of the hallmarks of how it moves forward.

It should provide a real boot in the backside to firms and individuals who might want to skip Vista for Windows 7, but who were otherwise concerned about upgrading applications.

-----------------------------
BY Glenn Fleishman
Source：TidBITS

Copyright © 2009 TidBITS Publishing, Inc.