Update: I have removed a major part of this post since the extension mentioned here was not so clean;). I have another extension that you can install, with much more functionality, and straight from the Google Chrome Web Store.Â Check it out here.
Once installed, the extension will add a Facebook icon on top of your Google Plus page which gives access to your facebook stream from G+. Installing this script is pretty much easy and takes only few clicks. Â The Google+Facebook extension is currently supporting Chrome and Firefox only.