Google-backed researchers Shumeet Baluja (pictured) and Yushi Jing presented the Mountain View company's latest image search and recognition efforts to an audience in Beijing, China on Thursday. VisualRank attempts to do for images what PageRank has done for typical Web pages — rank them in search results according to "authority," which will presumably increase the relevance of results. Problem is, their limited success came at a cost Google is typically loathe to pay: 150 units of homo sapiens who helped sort and rank the images by hand. Munjal Shah, CEO of image-search startup Riya, remarked to the Times: "I think what they're trying to accomplish is largely impossible." Funny, because large-scale, advanced image recognition is what Marissa Mayer says will solve Street View's privacy conundrum.