Awesome plugin, thanks for developing it so soon after Google+ made this available!
One small suggestion if I may:
Many people that are active on Google+ will have Google Authorship already setup and in use for their site. But if you really want to roll this plugin out to the masses, I think it could be an idea to make that requirement a bit more clear, if only to avoid countless support requests like "it doesn't work!"
Furthermore I like the way how you respond to feature requests by releasing frequent updates with enhancements.
For anyone looking for a smooth commenting system with social media integration, while at the same time not losing the default WordPress comments: look no further and hit the download button!