The votes are applied within the individual gallery category (not by genre). As a member, you can vote for as many images as you like, in any gallery. Only one vote per image will "count" during a week's period. What do they add up to? Images with the highest number of votes during any week are displayed in the "Hot 20" list for each gallery. Just select a gallery (not "all"), and you'll find a link for the "Hot 20" for that gallery.