Sounds exactly like how it works on Slash Dot. Not really a fan of that myself.
When the community is as small as vgChartz's is, you tend to learn pretty quickly as far as what users make interesting or amusing posts and what users annoy you. This works against a +/- system though.
It'd be like making a website devoted to Vikings and Packers. Give that a +/- system and all the Packers fans will vote each other up while all the Vikings fans will vote each other up. Of course, they'll also be voting each other down. The more heavily divided the userbase is, the less useful a +/- system will be. As we see on a daily basis, vgChartz is quite divided.
In the end, I think such a system would be more trouble to implement than its worth.







