As of September 30th, we’ll be turning off track changes in Reader. While this isn’t a widely used feature, we wanted to let you know in advance so you can set up a suitable alternative (such as http://page2rss.com). Your previous updates will not go away, but you will stop receiving new updates from any custom feeds you have set up.
We apologize for any inconvenience this causes -- and as always, please feel free to visit our help forum if you have any questions.
Update: You can use the Page2RSS transition tool to convert your feeds here: http://grtransition.page2rss.com/