Why should one member's vote be any more important than another? Someone who has just joined this site before could be a total chocoholic who has tried every bar going, whereas someone who's only tried 20% of the bars listed but has done lots of voting would be considered a 'better judge'.
Well it would encourage people to stick around.
Also, I think the ranking system doesnt help this site, I've rated 16% of the chocolate bars on the site and none of my squares are filled in. It needs to be less linear imo. eg after 5% you get one square, 10% 2 squares, 20% 3 squares, 40% 4 squares and 80% 5 squares.
At the moment I expect most people come here, rate a few, see no changes, get a bit bored and bugger off never to return.