I have added Facebook Connect functionality to the forums. If you use Facebook, you can click the icon at the top of any forum page and follow the instructions.
If you are a GP member and already have your profile and everything set up, you will need to UNCHECK most of the boxes in the setup process.
Once done, you can easily share your forum activity on your Facebook page with all your friends etc.
There is also 'like' functionality for all forum threads now as well.