Rated 3 out of 5 stars
I find it useful for seeing how many unread items I have. It would be better if it checked if there was a GR tab open already, and if there was, switch to it, rather than opening a new one. :)This review is for a previous version of the add-on (18.104.22.168-signed.1-signed).
Actually it does :) If you click on the icon it should switch to the opened Google Reader tab if there is any. If it doesn't work, it's a bug, then please provide me some more information. You can find contacts on the add-on's page. :)