Nice rundown from Mat Honan at Buzzfeed:<p><a href="http://www.buzzfeed.com/mathonan/googles-new-photos-app-is-like-gmail-for-pictures#.ofXNOoEv" rel="nofollow">http://www.buzzfeed.com/mathonan/googles-new-photos-app-is-l...</a><p>> <i>I have a cousin who I only have a few photos of. In almost all of these, mostly taken last year, she is 30. In another, from 2000, she is 16. But it’s the earliest one in the cluster that’s remarkable. In that picture, my cousin is only 4. Google Photos successfully matched a 4-year-old child’s face to a grown woman’s, with only a lone photo at 16 to tie them together.</i><p>> <i>Places are also useful. Photos looks at a variety of signals for this, including geodata from photos. But thanks to the wealth of geographic image data Google has amassed, it can also put your old, untagged photos on a map based on landmarks that appear in them. It reliably placed many pictures I had taken in Singapore more than a dozen years ago into a cluster, for example.</i><p>> <i>This makes Photos very searchable. It’s easy to find places in your pictures — even ones that aren’t geotagged. It’s equally easy to find very specific things, like Labrador retrievers, poodles, and caves. Photos also allows you to search for pictures of people doing things. I found people in poses when I searched for “yoga,” pictures of people with booze, coffee, and Coca-Cola when I searched for “drinking.” Sometimes the results are odd: photos of both wide smiles and crying faces when I searched for “laughing.”</i><p>Finally, the amazing deep learning imagery algorithms Google and Stanford demonstrated last year [1, 2] are available for consumer benefit. But yes, it really does seem like "Gmail for Photos", in that so much more of your life is now knowable by Google.<p>edit: further reflection...I have probably a TB worth of images of me and my friends over the past five years. I've done a decent job of labeling the folders every time I move files off of my camera and into Lightroom...but the thought of going through all the folders and sorting and tagging them seemed like something I would wait to do in my old age when it's time to make sentimental scrapbooks...Google Photo seems like something that could revolutionize that chore of finding photos of remembrance (for a wedding, funeral, graduation, etc)...on the other hand, it will most definitely have the power to connect everyone to photos taken by their friends, simply through the networks inferred from GMail/G+/etc...I think for the sake of my friends' past assumptions of privacy, I'm going to sit out on using Google Photos for my old photos...but I imagine in the future, we'll be less surprised about how we were auto-tagged in someone else's camera phone.<p>[1] <a href="http://arxiv.org/pdf/1411.4555.pdf" rel="nofollow">http://arxiv.org/pdf/1411.4555.pdf</a><p>[2] <a href="http://cs.stanford.edu/people/karpathy/deepimagesent/" rel="nofollow">http://cs.stanford.edu/people/karpathy/deepimagesent/</a>