To introduce users to the 'Like' button, Facebook has posted an alert that appears on users' Facebook pages and directs them to a FAQ section with information about the new feature (see screenshot below).
Facebook explains why it scrapped 'become a fan' for 'Like:'
To improve your experience and promote consistency across the site, we've changed the language for Pages from "Fan" to "Like." We believe this change offers you a more light-weight and standard way to connect with people, things and topics in which you are interested.
The new 'Like' button will help users take advantage of and connect to the Community Pages Facebook is introducing--pages that are to serve as the 'best collections of shared knowledge.' (more about Community Pages here.)
'Liking' a Facebook Page isn't the same as 'Liking' a link, video, or status update a friend posts.
'Liking a Page means you are connecting to that Page. When you connect to a Page, it will appear in your profile and you will appear on the Page as a person who likes that Page,' Facebook says. 'On the other hand, when you click "Like" on a piece of content that a friend posts, you are simply letting your friend know that you like it without leaving a comment.'
The 'Like' button that appears on Facebook may be just the first step: there are rumors that Facebook plans to introduce a 'Like button for the web.'
The New York Times outlines the concept:
The Like button will allow Facebook to keep a record of what a user linked to, providing the company with ever more data about people's preferences. Facebook, in turn, plans to share that data with Web publishers, so that a magazine Web site, for instance, may be able to show users all the articles that their friends like.