Please don't use it, don't give them your data and control.
What data are you referring to? Afaik, the only data it passes is the URL and how many times a FaceBook user loves your web page. How does that cede control?
This is a widget that sends traffic. It's a tell-a-friend widget. If you have a fear about this tell-a-friend widget, instead of posting that it's "stupid" please state the specifics of why this widget is harmful or not beneficial. Nobody in this discussion has detailed WHY this widget should be avoided. If there is a reason to FEAR this then it would benefit the community for someone to state the details. So please, someone, anyone, please state the facts of why webmasters should not use this tell-a-friend widget. ;)
My personal opinion is that this is a GIFT. It's an opportunity to add an additional traffic stream to a website. The purpose of this widget is to enable Facebook users to promote your website. In my opinion that's a good thing, it's a GIFT.