Flickr have introduced a new feature – collections. You’ve always been able to gather your photos into sets, but as people commonly have thousands of photos in Flickr, that’s a bit limiting. You can now gather your sets into collections. A collection is just a ‘container’ for sets.
It can go deeper than that – a collection can also contain other collections – up to five levels deep. A set can be in more than one place, too, which could be helpful. You could have a Personal collection, and a Places collection, both of which contain a set of photos of your house, or you could have a People collection and an Events collection, both of which could contain your set of wedding photos.
There are even new ways of arranging your main photos page – the first page people usually see for you. You can replace the sets on the side with these new collections, or you can get rid of the sidebar entirely. And, if you prefer, you can swap the two (or three if you have no sidebar) columns of small images for a single column (two if you have no sidebar) of medium-sized images. People see less of your photos that way, but they might get a better chance to appreciate the ones they do see.
I don’t think it’s a huge deal – nothing massive has changed, just a new preference for the home page, and a way of putting sets in other sets. It does really change the way you can organise your photos, though. I’ve just spent some time shifting mine around, and letting them spread out a bit more. For people who upload lots of photos to Flickr (I only have 1,077 on there so far) it’s going to be a really useful change. I’ve seen people with twenty or thirty sets, and it becomes quite awkward to navigate around. Collections will help with that a lot.