Facebook has made a small change to the functionality of its Like button that makes it more like the Share button. Now, when you click the Like button outside of Facebook, a full News Feed story (with a headline, caption, and usually with an image) is published with higher prominence on your Facebook feed. The tweak is expected to transform the way Facebook users share content via the social network, and on the Internet in general.
Previously, when you clicked the Like button on a third party website, a one-line Recent Activity story appeared on your Wall that often went unnoticed by your Facebook friends. Full stories were only published if the website chose to implement the "Like with Comment" version of the button.
Now, all versions of the Like button publish a full News Feed story, whether a comment is added or not. The change also appears to have been applied retroactively, though not for everyone, meaning that older content linked via the Like button also appears as a full News Feed story.
The new functionality is identical to the Share button, which means the Like button is essentially replacing the former. Despite this, Facebook has not yet killed the Share button; it is simply recommending that developers and publishers use the Like button.
The upside to this change is that using the Like button will likely generate more referral traffic and boost awareness to the link in question. On the other hand, if you use the Like button frequently, your Facebook feed may be overrun with stories and your Facebook friends may not be so happy. Something had to be done though as having two buttons was confusing and unnecessary: most simply did not know, or did not care, that the Like button worked differently than the Share button.