I gotta ask...If it's just like clicking on a thread found on Google, Yahoo etc, and if doesn't give access that they don't already have, and doesn't add any features that were not already there and if the same exact people can view the same exact data as before.....then what is the point of having the Facebook "Like" button?
That is a good question. I am not sure how familiar you are with Facebook, so I will just assume you have no experience with it and explain. When someone likes something, it is akin to them saying to their friends/family "Hey, I like this.". Their friends and family will see that on their Facebook page. They may click the link to see more about what it is their friend likes. That of course drives more traffic here and (hopefully) increases traffic and participation over the long term.