Firefox Extension Read It Later pushed out a big update on Thursday which adds deep integration with Google's Reader product. With the new version installed, a little check box shows up on the left of every single feed item, which you can simply click on to mark for later reading. Previously the only way to do this would be to open up the actual site from Google Reader, then click the Read It Later button.
To make going through that list of saved stories more manageable, you can now sort it by PostRank--a service we checked out back in July. Using this, Read It Later will tell you which of your stories are most worthy of your time based on things like traffic, user comments, and sharing on social news sites.
PostRank may not dictate which stories are really the best, but if you're an RSS newbie with a lot of feeds this is a nice editorial add-on. If you really like its recommendations, you can also install a separate extension which shows each item's PostRank right in Reader.
One of my favorite parts of Read It Later is that your saved list of stories can be accessed from multiple devices using a centralized RSS feed. You can access this feed from any browser (including Safari on the iPhone), and save items for later on using nothing more than a bookmarklet.
The quiet killer feature of this extension is still its offline viewing functionality. There's a new option to automatically have things saved to your browser cache, instead of having to select them one at a time. Under the old system, items you had not selected for download would appear dimmed out when attempting to view them without a connection. Combine that with offline Reader access using Gears and you can fill up a flight or long train ride with plenty of feed reading.