Keith's note: Some new images were posted at nasa.gov tonight. Have a look this image. Specifically, look at the direction labels inside of Node 3 ("Tranquility") that have been covered up (partially). On the right hand side of the image you can see an arrow that says "-> to HAB". On the left hand side you can see directions "<- to CRV". "CRV" usually means "Crew Rescue (or Return) Vehicle". "HAB" refers to the habitation module. Both of these things were deleted from the ISS program many years ago.