First thoughts were, why should I submit these ideas or stocks. Why should I really trust people's advice based on karma? I would rather see people ranked by the accuracy of their predictions.

Perhaps when you submit a stock or vote on one during the week it could record the current price and after a few days your karma points are based on the new price of the stock.

I also think you should have links to the stock price. I'm too lazy to type in all the ticker names into google.