|The Ethics of Facebook Like button|
Facebook is not exactly well-known for being a paragon of privacy protection, and now their 'Like' button is drawing scrutiny from privacy watchdogs. The Like button uses an iframe, so Facebook can track Facebook users via your website, whether they're logged in or not, and whether they actively click the Like button or not.
Facebook claims that the tracking data is anonymized, is not shared with 3rd parties, and will not result in contextually matched advertising.
Right, so I guess a non-issue...
Answering the questions: Yes/No. Yes. Yes. Yes/No.
I always assumed, to be able to target ads better to its users, was the main reason for FB to create that button in the first place.
<fb:like href="http://ecommercedeveloper.com" layout="standard" show_faces="true" width="400" action="like" font="segoe ui" colorscheme="light" />
status : true, // check login status
cookie : true, // enable cookies to allow the server to access the session
xfbml : true // parse XFBML
3. Insert into head
<meta property="og:site_name" content="insert your site description"/>
<meta property="og:image" content="http://www.yoursite.com/share-image-you-want-to-show-up.jpg"/>
The thing is facebook wants to dominiate the internet like google has done. So, its pretty imperative for them to track down everything so that they can use it for their own profits.