Editor's note: This post was updated on September 23, 2011, to add more information about Timeline and how it can be customized.
1. Real-time updates with Ticker
Dubbed "the Facebook within a Facebook," Ticker shows you what your friends are doing in real time in a box to the right of the News Feed. You'll see minor updates like new friendships, likes, comments, and other lightweight activities, while more important activities are reserved for the News Feed.
With Facebook's new apps (see below), you'll also see app activity, exposing what songs your friends are listening to, what movies or TV shows they're watching, which articles they're reading, and more. Just hover over an activity and a box will pop out with more details and the options to comment and like.
Many users are already calling Ticker invasive, as it gives your friends a play-by-play of everything you do. So if you want to prevent apps from sharing your activities, you can adjust your settings . Alternatively, you can remove app activity from the ticker on a story-by-story basis by clicking the "X" in the upper-left corner of the post when you see it.
The ticker can be annoying and cluttering, so if you want to remove it from Facebook entirely, here's how.
2. Changes to the News Feed
Facebook's News Feed, the first thing you see upon signing in, is no longer split into "Top News" and "Most Recent." Instead, you'll see what Facebook considers the most important stories at the top, marked with a blue triangle. These updates include posts from friends and Pages, photo tags, friend requests, event updates, and group activity.
If you haven't visited Facebook in a while, you'll see updates that Facebook thinks you'll find interesting, followed by recent stories below. If this new setup doesn't appeal to you, check out our guide on how to restore the "Most Recent" news feed.
Top News stories are marked with a blue triangle, which you can click to unmark the post as important. When you do this, Facebook will improve over time and get better at giving you relevant news.
3. Your profile is getting a redesign
Facebook is rolling out an entirely new profile design called "Timeline." It won't be available for a few more weeks, but you can sign up for it here.
The new Timeline profiles are wider, and place a big emphasis on photos and app activity.
Your profile begins with a large photo at the top. Below that is your general information, a status update box, and then a timeline of your activities. You'll see photos of you, status updates, life events (like a new job), and activity from any apps you're using (like Nike+, FarmVille, or Foodspotting.)
Unlike the previous interface, your friends will now be able to look back on your past activity, all the way to the moment you joined Facebook. The farther back you go, the fewer stories there are, bringing activity from the most recent years center stage.
Facebook will automatically decide what stories should be featured in your timeline, but it's completely customizable. To make a post more prominent, hover over it, click the star, and it'll be made wide screen.
You can also remove posts you'd rather not share by hovering over the story, clicking the pencil, and selecting the option to hide it.
Alternatively, you can view a simplified version of your entire Facebook history by clicking "View Activity" at the top of your profile. In this view, you can hide, feature, or delete posts from your Timeline.
Once you've pruned your Timeline to your liking, you can start adding what Facebook CEO Mark Zuckerberg called "life events." Because not everything in your life was shared on Facebook, there's an option to retroactively add events. Just click on the place in the timeline where the event happened, select the event type, and fill in the information.
There are many options for life events, including "learned a language," "got a license," "traveled," "broke a bone," "had surgery," "overcame an illness," "bought a home," "new vehicle," "got engaged" (and all the other relationship events), "graduated," "military service," and more. You can also customize your own events if they don't fit into the predefined ones.
4. New, integrated social apps
Previously, if you were to track a run with the Nike+ app and share it on Facebook, your activity in the News Feed would take friends to another Web site, where they could see more info about your activity. Now, services like Nike+ will be integrated with your Timeline. So the next time you track a run, the activity and a map of your run will appear on your profile--there's no need to leave Facebook.
Most of these apps will be "lifestyle" apps, like Goodreads (share what you're reading), Foodspotting (log what you're eating), and Foodily (share recipes and let friends know when you're cooking).
An important thing to note is that apps no longer require approval each time you share activity. Once you install the app and authorize it to post stories on your profile and News Feed, it'll never ask for your permission again.
Facebook is trying to create what Zuckerberg calls "serendipitous experiences," which let you discover movies and TV shows, music, and news that friends are watching, and allow you to consume them without leaving Facebook. Here are the details:
Listen: Facebook has partnered with Spotify, Mog, iheartradio, Rhapsody, Rdio, Turntable, Earbits, SoundCloud and Slacker to help you discover new music and listen to songs with friends. When friend listens to a song, you'll see his or her activity show up in Ticker. If you click that activity, you'll get more information about the song, and the option to listen to it with your friend in real time. Once you do that, your friends will be notified of your activity and will have the opportunity to do the same.
Watch: Like music integration, you'll also be able to watch movies and TV shows with friends. Facebook's partnership with Netflix and Hulu will allow you to share what you're watching in the News Feed and on your profile. If a friend sees your activity and clicks it, he or she can immediately start watching with you.
Read: If your friend is reading a news article in The Daily (one of the publications Facebook is partnering with), you'll see his or her activity in the News Feed. Click on that activity, and the article will appear within Facebook.