It can't track anything unless you login and allow Meebo facebook application to your profile. Just having the bar doesn't track anything.
If you are worried about facebook like feature and don't want anyone to find out about your likes and dislikes; then just set your appropriate privacy setting in your profile account. Go to Account Settings -> Privacy Settings ->Friends, Tags and Connections
Then set to appropriate level, preferably "Friends only" for "Things I Like".
There is nothing to be paranoid about. Like anything else online, you should only participate in things that seems appropriate to you. If you are not comfortable with facebook privacy, then don't use the toolbar sharing. If you have already allowed the toolbar to log you into facebook, you can deactivate it by disallowing Meebo app from facebook account->privacy setting->Applications and Website.
BC is not tracking or forcing anyone to use Facebook. The toolbar at the bottom is just a helpful feature for the members who find sharing and communicating with their facebook friends important.
They said, "After we turn into bones and fragments, we get resurrected anew?!" Say, "Even if you turn into rocks or iron.[17:49-50]
Cold Fusion occurring via quatum tunnelling in ~101500
years makes everything into iron