Profile Covers!!! Everyone should have this new function in their user account drop down menu. You should see the option to Upload Cover. Find a picture and upload it. There is a minimum on the size and the picture needs to be at least 850 pixels of width. I do believe the width is the main concern. So, go have fun decorating your profile page with something you like.
Not a bug but just something new. If you do however notice a bug within the function, please let us know.