Microsoft is simply spoiling its users when it comes down to the evolution of the core of the Windows client.
Both the first service pack to the latest Windows operating system available on the market and the next iteration of the Windows platform come with new kernels. Vista SP1 was released to manufacturing on February 4, 2008 and to the general public on March 18. The first taste of Windows 7 was delivered in January 2008 with the Milestone 1 build, while the operating system was confirmed to be under development until 2010. But both Windows releases have something in common, as they each bring to the table a new kernel.
"This is the first time we've ever had a common codebase for Windows that goes all the way from a budget consumer PC right up to a mainframe-class datacenter server. Internally to Microsoft, this makes it easier for us to provide sustained engineering on the product: if we want or need to update a system component, we only have to produce two binaries (x86 and x64) for all languages and product editions. Compare that to the days of Windows XP/2003, when we had maybe 25 different language editions and x86 and x64 variants for both client and server OS releases, and you can see how the testing matrix has become a lot simpler! Externally, the benefit is of course that simply by updating to SP1, you get the benefit of a kernel that has been through an extensive server-hardening process," revealed Tim Sneath Microsoft resident group manager for client platforms.
In terms of the kernel evolution, the next version of Windows, which at this point in time is yet to be a standalone package having to install on top of Vista SP1, will be synonymous with the complete overhauling of the operating system's core. Microsoft has been working since 2007 on stripping down the Windows kernel by removing all dependencies with the rest of the operating system.
The process gave birth to MinWin, which will act as the new heart of Windows 7. Even as early as 2007 MinWin was occupying just 25 MB and runing with 40 MB Ram, according to Microsoft Distinguished Engineer Eric Traut.