Problem will be number of posts per day. There is gonna be huge number of products everyday and some gonna buried down not because of there are not good but there are not so visible - timezone problem.
What about a system where, if a product gets a certain amount of upvotes, it gets pinned to the top. So maybe there could be 10 or so products that get pinned to the top each day because they hit a threshold of upvotes, with the rest battling for a spot on the pinned list every day