I've been using this plugin and it's been great. One small (but potentially getting large) issue: I would really like to have the ability to exclude specific pages. Here's the primary reason: for some pages, you don't want google to index your content. However, if you have +1 activated in the plugin, then google will ignore the noindex meta tag and indexes it. The reason for them doing this is simple: if someone +1 a page, they need to have the ability to show to page later to that person and/or someone in his social network.
There's also a little bug: when the plugin is activated, but it isn't being used, then there's still an empty container resulting from the padding and width properties.
Also, last, but not least: two small features request. Would you please integrate an email and a print button?
(Sorry for the multitude of topics, I figure I should say my piece in one post.)