Below are a few thoughts that I've had relating to a few points in the FAQ that need to be cleaned up by the site administration to prevent confusion when people move between Stack Exchange sites (especially between StackOverflow, ServerFault, and SuperUser).
The use of "power user" is confusing and should be clarified. I don't feel that "power user" encompasses enough people. There are plenty of people who use a computer on a regular basis and simply want to become more efficient. To me, these aren't "power users"; a true power user would be someone who you see using the command-line all the time, has automation routines for recurring tasks, and is comfortable to open the registry of a Windows OS and start hacking away. I think that the phrase "enthusiast" is sufficient for the scope and would bring SuperUser more in line with StackOverflow, which is designed for the professional programmer as well as the hobbyist.
The descriptions of what StackOverflow and ServerFault are need work. "Server" has multiple meanings, depending on if you are talking to a system administrator/network administrator or a computer scientist/software engineer. Programming also has different meanings - writing automation scripts might be appropriate on SuperUser or ServerFault and not StackOverflow, depending on the exact context of the question.
As new Stack Exchange sites open, I feel that it is important to potentially develop partnerships with them to offset some loads. A particular Stack Exchange that covers a subset of system administration/network administration/IT topics should be linked to in the official FAQ to ensure that people can get to the best possible venue to answer their questions. The topicality of each SE that is linked to should be described clearly (without ambiguity), but concisely.