You mean fused to the lcd and digitizer (as almost every iPhone has been) or are you saying it looks like the entire display assembly will be glued into the body itself?
If the latter, what makes you say that?
Yes, the latter. If you look at the current display glass on the 5S it has a small band surrounding the entire display and the entire display is ever so slightly raised above the the chamfered edges of the frame.
If you look closely at these new images there is a slight recess for the new display assembly to rest inside of the frame and form a smooth transition from the edge of the display to the frame. To my eye, the only way to secure it is with adhesive on the flat sections just below the small recess all the way around the frame.
If you've ever taken apart an iPhone 4 or 5, when you remove the 2 bottom screws the back of the phone then slides upward ever so slightly so you can remove the back. This new frame is all one piece (no back to remove).