This looks to be very interesting. Paul Thurrott and Rafael Rivera are revealing information on what has been called a ““secret featureÃ¢â‚¬Â of Windows 7 that is due to be announced officially when the Windows 7 Release Candidate rolls out.
It is called Windows XP Mode (XPM) and the purpose is to change the backward compatibility issues that each new Microsoft OS release has to deal with.
Here’s a quote:
XP Mode consists of the Virtual PC-based virtual environment and a fully licensed copy of Windows XP with Service Pack 3 (SP3). It will be made available, for free, to users of Windows 7 Professional, Enterprise, and Ultimate editions via a download from the Microsoft web site. (That is, it will not be included in the box with Windows 7, but is considered an out-of-band update, like Windows Live Essentials.) XPM works much like today’s Virtual PC products, but with one important exception: As with the enterprise-based MED-V (Microsoft Enterprise Desktop Virtualization) product, XPM does not require you to run the virtual environment as a separate Windows desktop. Instead, as you install applications inside the virtual XP environment, they are published to the host (Windows 7) OS as well. (With shortcuts placed in the Start Menu.) That way, users can run Windows XP-based applications (like IE 6) alongside Windows 7 applications under a single desktop.
The idea here is that Microsoft can begin to discard technology that exists for backward compatibility by including XPM and yet still claim Windows XP compatibility for those that need it.
Paul Thurrott has a series of pictures up about this.