An internal alpha build of Microsofts next version of Windows, code-named Longhorn, made its way onto the Internet early Tuesday.
The leaked build, which is numbered 3683, appears to be from late September and sports quite a few new feature concepts—although many are not yet functional.
Microsoft experienced a similar leak during the alpha stages of Windows XP, then code-named Whistler.
News of a leaked Longhorn build cropped up late last month when screenshots posted to Windows enthusiast sites purported to showcase the next-generation operating system. But the select few with access to the code initially opted to keep it under wraps rather than risk incurring the wrath of Redmond.
Although Longhorn is in its very early stages of development, the leak provides a rare glimpse into Microsofts future plans. The leaked alpha build has received a slight interface makeover from Windows XP and includes a very rough new Visual Style dubbed "Plex."
The oft-rumored Longhorn Sidebar can be enabled via Taskbar settings and uses XML to display customizable tiles such as a clock, virtual desktop manager and Internet search. The Start Menu can also be docked within the Sidebar, completely removing the Taskbar that has been a staple of Windows since 1995.
Changes under the hood are just beginning to show in Longhorn. Microsoft has replaced the standard Display Properties dialog with an incomplete XML-based configuration panel that utilizes a new API framework, code-named Avalon.
Longhorns new WinFS file system is included in the alpha build, but the services are not yet functional and cause immense performance degradation while active.
Even with many core features still incomplete, a telling sign of Longhorns significance comes in the form of the simple "About Windows" dialog box. The new operating system identifies itself as Windows 6.0, a large departure from Windows XPs 5.1 designation.
Microsoft has not yet set a release date for Longhorn, but sources place a final version in late 2004 or early 2005. However, any current plans could drastically change as development of Longhorn progresses.
The final release of Windows XP, for example, only bore a slight resemblance to early Whistler alpha builds.