After receiving a lot of backlash from the community, Microsoft reluctantly agreed to open up certain parts of the Vista kernel to software developers, making it easier for them to create software that will work with it. Security software, in particular. Only two months after that agreement, they have delivered. In a statement released yesterday, Microsoft has delivered Vista kernel APIs, both the 32-bit and 64-bit sections of relevant code. It should give these companies exactly what they want:

The APIs will offer security and nonsecurity software makers the ability to develop software that extends the functionality of the Windows kernel on 64-bit systems in a documented and supported manner, without disabling or weakening the protection offered by kernel patch protection, Microsoft said.
This isn't everything they asked for, though Microsoft still intends to release updated versions in the future, during the release of Vista Service Pack 1.