This site's Spring launch was marred with a lot of poor, short, not very helpful answers. Forum level, discussion type answers where an upvote more often meant "I agree" as opposed to "This is useful." Looking around I think, and hope, we've come a long way.
For reference, here's some discussion on the topic of answer quality:
Yes, I asked like half of those myself; it was something I was very concerned with early on, and a big part of why I wanted to help get this community into shape by becoming a moderator. A problem is moderator powers don't really help moderate bad answers. I can't close an answer as a warning you need to fix this before anyone can benefit; I can leave one of a couple of Post Notices, I can downvote (believe me I do) or I can delete/convert to comment, for those answers that aren't remotely answers. But that doesn't do much,
The tone and attitude of the community is what really makes the difference when it comes to answers; lots of simple, chatty or otherwise unhelpful answers sends the message that these are accepted. See The Broken Window Theory.
Since the tone we set is so important we went and added some answer quality guidelines to the FAQ. We've also aggressively closed vague, discussion-y or not constructive questions. Plus we've had a dozen or more Meta questions on this topic. I'm not sure what mix of those worked, but I really think the issue has improved dramatically.
So, have we really improved? Are there still answer quality issues? What more can we do?