Photos in the test design get much larger real estate within each tweet.
Photos and video get a section of its own.
Twitter user bios are scaled left in the test design format and header photos are significantly larger. The look is very reminiscent of Facebook and Google+.
Bio information resides under the user's profile photo.
The "following" and "followers" sections embrace a card design approach.
How tweets look as you scan down the timeline.
Tweets are not just vertical anymore, but scattered across the page.
Only updates are made to the profile pages. The homepage looks the same.
A look at the Tweets and Replies page.
The card format is used for the favorites section too.
A look at the new Twitter Lists page.
A look at the Edit Profile section.
Twitter is still making tweaks to the profile redesign experiment it's testing among a small group of users, such as returning to a vertical timeline and making pictures even larger.
Last night, Mashable assistant features editor Matt Petronzio — who first spotted the major update to his Twitter profile page — noticed that the layout changed back to a single vertical stream. Previously in the test, various-sized cards showed up scattered across the page. But as of this morning, they are back to the way they are pictured in the screenshot below.

One of the biggest design complaints from readers who read our original story was that the look was too reminiscent of Facebook, Instagram and Google+, and they disliked Twitter's potential move away from the vertical stream.
Petronzio's most-recently tweeted picture is significantly larger this morning too.

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Although Petronzio isn't verified on the site, there's an option for the stream to show "Tweets" and "Tweets and replies" for every user — a feature typically reserved for those with the blue check mark.

Updates appear only to affect his profile page and not his homepage.

The news comes days after Twitter rolled out its latest design to all users, after weeks of behind the scenes testing.

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