On stackoverflow i answered a lot of questions by people with a very low reputation. Basically, most of the questions were my answer is accepted but no upvote is given. This is usually because the poster hasn't the right to vote up yet.
Usually when your answer is accepted you get 25 points (15 for the accepted answer and 10 for the upvote), when you answer a question of a first time poster usually you only got 15.
This is to say that maybe the system should give a bonus to the user whose answer is the "first" accepted answer of another user.
I think that trying to answer questions of people who post for the first time is more difficult (because usually the question is not well formed, etc. etc.) and takes more time and patience than answering other question, but providing an answer to those question is fundamental to keep the site going, because a good answer "hooks" an user in. For this reason i think that answering those questions should be encouraged
EDIT- this is exactly what i was trying to say: Shadow upvotes on own question for newbie users