Until now users had to either manually download a standalone installer or install from Windows Update manually. Only English, French, German, Spanish, or Japanese languages are currently being distributed automatically, however.

Also, it should be noted there are a few issues that may prevent automatic downloading from occurring, most prevalent of which is the "old driver issue," in which SP1 can't be installed because older drivers may cause an endless reboot cycle.

While Microsoft outlines this and other issues on this web page, why they haven't provided a tool that indicates a) which driver is the problem, b) where to get an update - if available - is beyond me. For most end users trying to search down which driver is the issue is beyond their capability.

And in that case, I would label Microsoft's automatic distribution of SP1 as "somewhat" automatic.

Source: By Tech Ex