Back in December, Google Reader announced that it was introducing a feature that let users share posts with anyone in their Gmail/Gtalk contact list. Unfortunately, the sharing was all-or-nothing – if you decided to share a post, it would be available to all of your contacts, as there was no way to single out a group to share a post with. This lack of control led to a privacy debate as a number of high profile bloggers wrote that Google Reader needed to include granular privacy controls. Google responded with a workaround option using tags, but it was inconvenient and unintuitive.

Today, Google Reader has finally implemented custom friends lists, which allows users to selectively share posts. However, while this will restrict who your posts are automatically shared with, the added privacy may not be enough for some people, as users will still be able to access your shared posts through a static public URL.

Along with the restricted sharing function, users can also choose who they’d like to received shared articles from. Whenever someone shares a post with you for the first time, Reader will give you the option to preview the post and then decide if you’d like to subscribe to future shared posts.