Google Reader is undergoing a constant update and its being transformed to compete with major social media websites like Del.icio.us and Twitter.
Add Notes:
Google Reader now helps add Notes on to it.
Item Sharing:
The new feature from Google helps annotate a shared item with your own notes.
Bookmarklet:
The new bookmarklet helps save any web page along with personal notes and share them with friends. The Google Reader bookmarklet helps save webpages which do not have a RSS feed.