It takes just 2 points (one vote from one person) to get something to the front page on hacker news.
Are you planning on increasing the threshold/required criteria, paul? It's not really necessary at this point, but do you have a plan in place for when it does become necessary?
Sometimes you can get a story on the reddit frontpage (for about 3 seconds) from one vote if you upvote the instant it was submitted. It'll go the same way here, where one vote just gets you to the front page for a very short time.