I have been using Google Reader for a while now. It is quite handy when one wants to be in sync with different feeds across different machines. Also, now it is possible to add feeds directly to it through Firefox 2.0, which makes it quite convenient to use. The other useful feature is the ability to share interesting entries. It is also possible to subscribe to feeds of others’ shared items.
In some ways, it is similar to social bookmarking, but the difference lies in the ability to browse and share the items of interface through a single interface. There is also a clip available which can be inserted into sites, similar to the dogear bookmarks. The import/export feature is also useful, as you can use Google Reader to transfer feed subscriptions across machines. Basic organization features include tagging and starring items. There’s also a mobile version available for those looking to read feeds on the move.