Music for infiltrating an evil fortress!
#catphoto That's not how you use chairs, Sophie!
With the upgrade we got a new feature: in user preferences, under appearance, you'll find a toggle for advanced mode. It lets you toggle between the current layout with multiple columns (advanced mode) and a more simplified mode with a single column, more closely resembling Twitter.
Advance mode is toggled for current users, while new users get the single column layout by default.
I think that worked? Let me know of any problems!