I just happened to notice NBC tweaked the window that looks into the newsroom. In this shot, taken the day the set debuted, the window is divided into two sections (it’s the gray vertical line camera right):

Now it seems that bar is gone, though I’m not sure when it disappeared.

Taking away that bar certainly gives the feeling that the studio is more connected to the newsroom, especially in the wide shots when Brian has a guest at the desk with him. However, that bar added a bit of visual interest and separated the newsroom from the Nightly News studio. The wider, uninterrupted window seems out of place; but perhaps that because I’m used to seeing the old version.