"Unanswered" are considered the questions whose answers have received no upvotes. This creates the following situation: a question gets answered, and answer is accepted by the OP, but the OP has not enough reputation in order to also upvote it. At the same time, the question may be so specific and narrow, that no member with upvoting rights upvotes it, due to lack of interest in the subject matter. Then the list of "unanswered questions" contains also this kind of questions, which in my opinion are not really "unanswered" since they have been indicated as useful by the OP in the only way the OP could indicate that (by the way, can somebody count how many of the questions with no upvoted answers have an answer accepted by the OP?)
I agree that some threshold for upvoting rights must exist (and it is set fairly low anyway, but still creates this kind of situation, especially for questions that come from new users), so shouldn't the "unanswered criterion" change so that questions with accepted but not upvoted answers stop appearing as "unanswered"?
Since this is, I think, a stack-exchange-wide feature, and so perhaps unlikely to change, should we go on a crusade to hunt for these questions and upvote them in order for them to leave the list of unanswered questions?
I believe there is a stronger case to consider these questions as "answered" compared with the questions that are essentially answered in the comments -in the case I am describing, somebody did post an answer.