Originally posted on Jetpack for WordPress:
If there’s one thing we’ve learned about the web, it’s that people really like to like things. That’s why the latest version of Jetpack introduces a “Like” feature. The new feature enables a “Like” area at the bottom of your posts and pages. A button allows your readers to show appreciation for your posts as well as save your posts for later viewing on WordPress.com using the Reader.
Once a user likes your post, their Gravatar will be displayed below your content, allowing you to engage with them further. You’ll also receive a notification in your toolbar if you have the notifications module enabled, and an email notifying you of the action.