I added the same thing to the forums yesterday, and a couple of people have the same problem. I have deleted my facebook account from wordpress and then relinked to it but still getting the same problem.
My guess is that it has something to do with changes to the Reader! They make a change in one place and it creates a problem in another! I bet that the system code is a real Frankenstein’s Monster! None of the recent changes have made improvements – they should leave well alone until they are sure how changes in one place will impact elsewhere!