The curator of the blog, Wagner, has done an amazing amount of work organizing more than 14,000 images into extremely useful reference categories for artists, such as: Heads, Hands, Teenagers, Children, etc.
And if you don’t follow the regular blog yet, be sure to check it out. It’s full of wonderful work, and especially great for those that are interested in animation and concept art. Wagner spotlights the work of 3 different artists each week. http://www.characterdesignpage.com