Facebook is testing a new format for user Timelines, which puts all posts in a single column on the left and any activity modules in a narrower column on the right.
This layout addresses one of the common complaints about the new profile: users previously had to look back and forth on the page as they scrolled through to read their stream. Some users found the two-column layout frustrating. With this design, the line down the center has been removed, making the profile look less like a timeline. However, the timeline of dates still exists in the top right of the page to jump to a particular month or year.Facebook Testing Single Column Posts On Timeline [insidefacebook.com]