SO and Severfault got their user base, which is a pretty apt one, by saying "Hey, the other helpsites aren't very good, and we can improve. A lot of smart people who read our blogs, so here, we invite you to join our site." I would suspect, then, that for the first n months, questions will be pretty good because the user base will mainly be the people who are already active on SO and Serverfault.
Over time, as more people come on board, it isn't inconceivable that we'll start seeing Yahoo-answers type problems: unclear questions, scant on details.
Many forums try to combat this by having a sticky "FAQ" thread, in which they take common questions and post them at the top, along with links to the relevant posts.
The other thing that happens is that people ask questions and nobody knows. This happens a lot when searching (for example) the Ubuntu forums - lots of problems specific to someone's hardware and video chip, and plenty of people who have the same problem, but nobody who has an answer.
So what is yet to be seen is this:
- Many forums have posts which say "I have this problem too! Does anyone have a solution yet?" Does the upvoting metaphor accomplish the same thing?
- Is upvoting an effective way to actually get someone to investigate the issue at hand?
- Will bounties and reputation also increase the chances of finding a good answer?
We know that this (usually) works for code-related questions. But taking the time to explain scheduling to someone when you already understand the concepts is different from doing the necessary research to figure out a display-driver problem. Of course, I say things like that because, to me, many of these things are a complete mystery.
So my hope is that, in contrast to ubuntuforums, superuser will help experts come out of the woodwork. But right now... its hard for me to even conceive that such experts exist!