Photostreams are a new way to share your photos on Flickr, on simple webpages where you control who sees what. All the photos you upload automatically go into your Photostream, but different viewers see different images, depending on their relationship to you.
How does it work?
* As always, you can make photos public or private. You can also restrict the viewing to people who you have tagged with a specific relationship ("only show this to friends or better").
* Public photos appear to everyone viewing your Photostream, but you can exclude any public photo if you'd like.
* You can also see the collected streams of your friends' photos at http://flickr.com/photos/friends/, and the latest public photos on Flickr at http://flickr.com/photos/.
Link [Boing Boing]