Popular Posts from Your Google Reader Subscriptions:
Depending on the number of subscriptions, if you don't visit Google Reader for 2-3 days, your reading list will have hundreds of new items. Google Reader doesn't provide a way to filter the items that are most relevant to you, so the best idea is to read the new posts from your favorite blogs and then go to "all items" in list view.
Another idea is to use the AideRSS extension for Firefox to restrict the reading list to the most popular items. AideRSS uses some arbitrary data that could measure the popularity of a post: the number of comments, Google Blog Search backlinks, del.icio.us bookmarks or the number of votes at Digg and reddit. All these values are used to calculate PostRank, a number from 1 to 10 that tells the popularity of a post among all the posts from the same feed.
Once you install the extension (or just the Greasemonkey script), AideRSS adds the PostRank value next to the title of each post and lets you filter the most popular posts. If you select a folder or switch to the "all items" view, AideRSS adjusts the ranking values based on the context.
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AideRSS also integrates with NewsGator and it lets you subscribe to the most popular posts from a feed: best posts from Google Operating System or from an OPML file.
{ via AideRSS Blog }