There's now more emphasis on photos and tweets that are getting favorited or retweeted. Just like Facebook, Twitter has adopted a timeline view. 

The redesign will roll out to people over the next few weeks, but new users will immediately see the new look.

Here's a quick summary of the new features:

Best Tweets: Tweets that have received more engagement will appear slightly larger so that your best content is easy to find.
Pinned Tweet: Pin one of your tweets to the top of your page so that it’s easy for your followers to see what you’re all about.
Filtered Tweets: Now you can choose which timeline to view when checking out other profiles. Select from these options: tweets, tweets with photos/videos, or tweets and replies.

Check out some more images: