Here's an overview shot from Google Maps:
https://www.google.com/maps/@33.9435...!1e3?entry=ttu
On the right, you can see the connector between TBIT and T4, which has been in place for several years.
On the left, the connector between TBIT and T3 is under construction and appears only partially built (this seems to be a pretty old image).
When I was at LAX recently, it appeared to be much further along.
As others have pointed out, it can't be completed soon enough.