Google Reader is already known as a good aggregator of the Long Tail of online content (e.g. blogs) as it makes it easy to subscribe to and manage feeds. Recently Google Reader has become a Long Tail filter as well. Steve Goldberg from Google Reader announced the newly added recommendation feature. He writes:
To help with the discovery of interesting sites to subscribe to, we just released personalized recommendations in Reader. When you visit our discovery page, you'll see quite a few feeds that we think you may find interesting. "Interesting" here is determined by what other feeds you subscribe to, as well as your Web History data, all taken into account in an automated, anonymized fashion. (To learn more about how our recommendations work, see our help article about them).
Another feature he announced is drag-and-drop support for subscriptions and folders. A nice feature indeed if someone has to deal with a big number of subscriptions.