It looks like the file Oculus_SDK_Overview_v0.01.pdf that is available directly from the front page is older than the file Oculus_SDK_Overview.pdf that is included with the SDK download. For example, the diagram on page 24 is missing in the stand alone version, and the SDK version has a lot more information in section 5.6.3.
Just thought you should know so people don't get confused. 😄
Also, in section 3.3 of the SDK overview there is reference to directories that don't exist, specifically Oculus\Tools - this directory doesn't appear to be there.