Microsoft released its latest consumer preview of Windows 8 on Thursday, giving potential buyers a good look at what’s changing in the next version of the operating system. The preview, which had been expected this month, came a hair ahead of schedule — which means Microsoft is likely on pace to meet an expected October release.

The preview helps fill out more details on why Microsoft has decided to blow up and rebuild its design sensibilities with Metro, a bright, blocky home page that pushes aside the traditional desktop.

Why would they do that? I’ve got one word for you: apps.

The new preview makes it even clearer that Microsoft is showcasing the work of its developers, adding more live apps to the home screen. Many of these apps update constantly, thus giving users the latest news, a quick look at their latest e-mail, etc. In other words, the preview shows off what actual advantages Metro can provide users.

As Ed Bott at ZDNet puts it, “The underlying operating system is solid, reliable, full-featured, and impressively fast. But it’s no longer the star. The apps included with Windows 8 are the true stars of the new OS.”

Not that apps are the only thing Windows 8 has to offer. For those who want the normal desktop, it’s definitely still there. It has a bit of a different feel, since everything in Windows 8 is meant to work equally well for touch controls as it does for mouse and keyboard.

“It’s impressive how well Microsoft has been able to replicate the touch workflow with the mouse and keyboard,” noted CNET editor Seth Rosenblatt. “I don’t think we’ve ever seen the two integrated quite like this before.”

Switching from desktop apps to Metro apps and vice versa is still fairly jarring, but that’s something that will change as more developers get on board with what Microsoft is trying to do. Getting developers will be key for Microsoft and Windows 8’s success — the company will need to build up an app store with a range of programs that approaches Apple’s store for the Mac.

Other features of the new build include support for Flash — which will distinguish Windows tablets from the iPad — and a default “Do Not Track” privacy setting for its Web browser.

The new setting has already drawn praise from the Federal Trade Commission, as my Post colleague Cecilia Kang reported.

“Microsoft’s Do Not Track option in its upcoming version of Internet Explorer is yet another step forward in giving consumers choice about their browsing data,” said FTC Chairman Jon Leibowitz, who urged the industry to offer consumers more choices about tracking.

The inclusion of Do Not Track is a bit surprising in light of Microsoft’s advertising business, something that the company’s chief privacy officer, Brendon Lynch, addressed in a blog post.

“Online advertising is an important part of the economy supporting publishers and content owners and helping businesses of all shapes and sizes to go to market,” he wrote. “Of course, we hope that many consumers will see this value and make a conscious choice to share information in order to receive more personalized ad content. For us, that is the key distinction. Consumers should be empowered to make an informed choice.”

With all the changes in place, the company will have to avoid is the same sort of backlash that greeted the last major rethink of is operating system, Windows Vista.

As Microsoft-focused blogger Paul Thurrott said in his write-up on the system: “Windows 8 is very much like Vista because it represents a sea change, a huge platform bet that will confuse and confound some, even while it sets up Windows for another decade of expansion.”

But this preview of Windows 8 seems to indicate that Microsoft has a clear vision of what it wants Windows to be and is marching toward its release. Meanwhile, the company will have to keep its focus to make its mark against Apple and Google as it fights for a spot in the tablet world.

“From the refinements in this release, it is pretty clear that Windows 8 will make its deadlines as a solid product,” IDC analyst Al Hilwa said. “Microsoft is optimizing correctly on this one by opting for their platform business instead of for Bing. With this move, they have an opportunity to build up the trust in their brand and differentiate it from Android and Google.”

Related stories:

Post Tech: Microsoft Windows 8 includes default Do Not Track privacy feature

The Verge: Windows 8 Release Preview: What you should know

Windows 8 preview expected in June