[jrockway]

What's more, there's a well-documented problem ("the fastest gun in the West") whereby the first semi-correct answer will quickly rise to the top, drowning out later (but more correct, more thorough) answers.

I haven't noticed this. I know I have personally answered questions months after an answer was accepted, and have gotten plenty of points. In some instances, the "accepted answer" was even changed to mine.

Stack Overflow's problem is that 80% of the answers are from talkative people with no clue, and 100% of the questions are from people who have never heard of Google.