Vista allows you to choose a "compatibility mode" for older programs but it has only rarely worked for anything I've had. The simplest way to set it up is to install the program, then put up a shortcut on the desktop. If it's a program that Vista identifies as "possibly incompatible," the "Properties" for the shortcut offers a Compatibility tab where you can tell it to "run as for" an earlier Windows version. WinXP had pretty much the same method for older software. Neither worked very well in most cases where you needed it.

The greater problem with Vista was with hardware, since there's no such thing as a "compatibility mode" for drivers. An entirely new, rewritten driver is required for Vista. If the hardware maker didn't provide a new Vista driver, the hardware didn't work.

Both Vista and WinXP had a sort of "compatibility update" feature if you did an upgrade from an earlier version. Both of these would attempt to "salvage" software installed at the time of the upgrade, by "filtering" the existing installation into the new one at the time of the upgrade. It didn't work very well for the upgrade to WinXP, and less well for the upgrade to Vista. About the only thing I've seen that worked with the Vista "upgrade filter" was the ability to automatically preserve Outlook Express email and address books and import them into the "Mail" program that replaces OE in Vista.

OE in WinXP and Mail in Vista are essentially the same program, but OE used a binary "address book" (.wab) and "email" (.dbx). Mail in Vista has an open .csv file for addresses (newly named "contacts") and a somewhat different setup for messages in which each message is more or less a separate .eml file.

The "virtual machine" method for backward compatibility reported in the article appears to be a variation on the upgrade "filter" method used by Vista. You do not run programs in a virtual machine. You start the VM to install the program, and then Win7 thinks it was installed in a former OS, and it's finishing an upgrade, so it attempts to "filter" the program into a form that will run in Win7.

Same old wheel. Different hubcap. The usual used car sales crew.

If it works better than Vista, it's possible that programs that ran in WinXP but didn't run in Vista might - just might - - just possibly might - - - there might just be the possibility that they might - - - run again in Win7.

It would be wonderful if this method allows you to use WinXP drivers in Win7, so that older hardware could be used; but I don't see any real promise of that being the case. The descriptions of the "feature" at this point are vague, and unofficial.

It might be worthwhile to save some old software and hardware, if it's something you liked and you've got a place to keep it, just on the possibility that you might be able to resurrect it by switching to Win7 when more is known. I don't intend to hold my breath while waiting, but may postpone junking the $400 scanner that can't be run with Vista. It might be possible to justify a new OS if I could get the scanner back and get full-featured use of the $360 Super-B printer. (They only make Toys-4-Tots now, so neither machine is replaceable with a "business strength" Vista-compatible machine.)

John