I've gotten a few emails about this piece of utter baloney, apparently because it's been Slashdotted. (Which says a lot about the quality of Slashdot, frankly.) I'd point out that 90 percent of the article is about Windows Vista and OS X for some reason. What it boils down to, however, is this:
Microsoft Windows 7 Exclusive
Windows 7 takes a different approach to the componentization and backwards compatibility issues [than does Vista]; in short, it doesn't think about them at all. Windows 7 will be a from-the-ground-up packaging of the Windows codebase; partially source, but not binary compatible with previous versions of Windows.
Or... Windows 7 will be a minor update to Windows Vista that will ship sometime between late 2009 and 2011. It will be based on exactly the same code base as Vista and will offer the same level of backwards compatibility as its predecessor. Just today, Ed Bott made an argument (that I don't fully agree with, incidentally) that the new MinWin kernel won't even be part of Windows 7.
Anyway, back to this post. There are no sources. And there's no real indication who this guy is or where he came by this information.
I would point out, however, that I've often argued that Microsoft should drop backwards compatibility, in effect creating a brand new OS. Doing so would require some form of compatibility through virtualization, which is certainly doable. But wishful thinking aside, taking today's Windows and stripping backwards compatibility out of it wouldn't actually result in better performance for "native" applications. Instead, Microsoft simply doesn't update older APIs while the oldest APIs drop off over time. It's a natural evolution.
And this bit doesn't even make sense:
Making the break from backwards compatibility is a dangerous proposal but a dream for software developers. Performance of native applications can be increased, distribution sizes can be cut down, functionality can be added without the worry of breaking old applications, and the overall end-user experience can be significantly improved.
None of this is true, and none of this requires breaking backwards compatibility.
Microsoft will continue to introduce new APIs. None of this means that older applications have to lose out. In fact, the natural break point for compatibility is, of course, the transition to 64-bit computing. And I'd point out that Microsoft has said publicly that Windows 7 will ship in both 32-bit and 64-bit versions.