The site launched into private beta yesterday, and we at the time of this writing have 44 questions. Of those, 9 questions have accepted answers.
I would suggest that we ought to be careful about accepting answers this early. While it is definitely nice to see that green checkmark next to one's answer, this is still very early in the process and we should expect new users who signed up to participate in the private beta to come in at least over the next several days. Do vote, however!
Particularly on lower-traffic sites it is generally suggested to wait at least a day or so before accepting an answer, based on that people live in different time zones and that questions which have accepted answers tend to receive less attention from the community.
This isn't something I or anyone else can mandate, obviously, but I feel it is something that would be worthwhile to keep in mind as we ask and answer questions.