Add an answer acceptance rate, too
I think it would be great to complement the the newly added "accepted rate" feature for the questioner with a "accepted rate" feature for the answerer.
Actually I thought this was the feature all about when I saw the announcement.
Current user reputation is a very good indication of how good a user is, but it has a direct relationship with the time spent on SO ( obviously better answers require less time spent in SO. Jon Skeet reaches it's 200 limit in two answers with 10+ up votes) .
Adding the accept rate from the answer side, will also encourage in the quality of the answer.