We've made a photosite in Drupal 8, we chose to do it in Drupal 8 to see how far Drupal has come when it comes to handling pictures and layouts. Everything went better than expected! You can see the result here: http://fageltbilder.se
We've built several other sites in Drupal 8 and it feels like Drupal 8 is very stable and we enjoy coding towards it. Several things which were very hard and complicated to do in Drupal 7 turns out to be a lot more simple in Drupal 8.
If you're going to create sites where you have to code a lot of modules and you don't have the need to use a lot of existing modules Drupal 8 feels like the natural choice. Now we know that Drupal 8 can handle photosites in a satisfying way.
Here you can enjoy Jörgen's photos.