We noticed recently that when folks (including ourselves) had both our PostRank Google Reader Extension and Read It Later installed (and we totally recommend both), they didn’t play well together in Google Reader. (Thanks to the other people who alerted us to this as well!)
Basically, the Read It Later checkmark sat on the PostRank score’s head and shoved the PostRank score down and they were just like squabbling siblings. So we said Enough! and sent them to their rooms.
And now the issue has been fixed, so we welcome you to download and enjoy both. 
(If you had a previous version of our PostRank Google Reader Extension installed, you will need to installed the latest version, which is 2.5.)