Voting For Articles Suggestion

I'm sure it has been raised before, but why don't we just have people rate the articles on a 1-5 scale? When a certain amount of people vote, you average the article score, and see if it's front page material. Here's my example:

Number of people for voting: 12

Score to make front page: At least a 3.5

If it's not making the cut, continue to vote until it's worthy enough for the front page.

Now, if an article is rated 3.5, makes it to the front page, then someone votes it down, it would still make it on the front page to prevent constant back and forth moving of an article.