With this new move, it seems that Flickr has made a turn towards the domain of 500px.com, also known as providing a stylish way of showcasing your photos. 500px actually used to have a design that was almost an exact match to what Flickr has now, and still looks remarkably similar.
I launched the beta of my own photo sharing site a few weeks back and the new Flickr design is somewhat similar in parts (flexible width/tiling photos). It seemed logical to me to adopt a Pinterest style grid for varying size images, rather than cropping them all to squares, though I notice that Flickr's design works more in terms of rows (https://www.flickr.com/search/?q=nature) than columns (https://photographer.io/categories/nature/photographs).
I'm very curious as to which style people find the easiest to browse.