I love this plugin and use it on several websites. One of the sites I have is using excerpts and in all the exerpts you see the text "tweet" when the plugin is enabled.
I guess the plugin is trying to show up in all my excerpts but excerpts remove all html from the text so that's why it's only showing tweet as text.
How to disable the plugin on excerpts?? Maybe an option for this should be added in future updates. The Addthis plugin has this option but I like the display of this plugin better.