When it comes to self-votes I like the approach Reddit has made. Every post and comment are automatically self-voted up. This way users don't have to wonder if it's OK for them to like their own posts/comments or not. As a bonus, instant +1 gives you this nice feeling that your post is net-positive. If it's not, people will vote it down. There's really no reason to start vote counter at zero. Also, apparently karma is not directly connected to upvotes.