Here's how it works:
1) It builds a list of the most thumbed photos in the past 7 days, sorted by thumbs (highest amount of thumbs at the top of the list).
2) Then it goes through the list and starts putting them on the page, disregarding any photos that are of genera for which 2 photos from that genus have already been shown.
So for example, if there are 8 photos of daylilies in that list, it'll show the top two and then disregard any other daylilies. Once a photo is more than 1 week old, it can not be shown in that area anymore.
