I agree with everything that is being said here. I would also add:
– Tag page, where tags are displayed, along with tag description. Page should be able to filter for tags that are most popular, lest popular, alphabetically etc.
– Option to subscribe for certain tags, where you will get notification if someone posted question with particular tag. I would love to really help people, but in current unorganized flood is really hard to find question I can safely answer, or question is already answered, Or I see question, refresh page, and it down the line and I just can’t find it.
– We need community moderation. With flood of users, you guys just won’t be able to deal with all traffic. I’m sure you will try, but we all have business here for Q&A site being clean and useful, for general knowledge sharing.
–Categories need to be clearly exposed. Preferable as tabs on top of page. When posting question, selecting proper category should also better expose. I personally would move the category selection to bottom, just above save button, and make it ListBox instead of DropDownBox. The letter look nicer, but it’s easy to miss and pick wrong category. More over by default category selection should be empty, and it should not be possible to post without selecting category. It also should be possible to change category when editing post. So I can for example correct my self if I choose wrong one.
–automatic email remained to accept answer for question. If the question have not accepted answer for X amount of time there should email send to person who asked question, to which will remaind of accepting answer. It should be possible to disable this on per question basis (but not globally!).
– it would be nice to strictly separate forums and Q&A site. Forums is for more general discussion, about whatever. Q&A site, should be only about asking questions that can be strictly answered, without any particular discussion. That is not to say, you can discuss in Q&A site. You can do so, but only using comment to question.
– this would be controversial, but I would personally made Q&A site only for subscribers, with only one section accessible for everyone. Everyone can read everything, but only subscribers can ask and answer question in most categories. non-subscribers could do it only in one category. This would really help controlling spam, repeating the same question over and over again, as well as improve general quality.
– Add title tags. When question is unanswered it could have appened [Unanswered] to the title automatically. If answer is checked it would have [Answered] appended instead. Color marking questions is also good idea.
–oh please increase character limit for comments 