Brittany wasn't there because her actor left the show because she was pregnant just had a baby.
Rachel does dress differently now that she is NYC that was definitely a visual cue.
Quinn wasn't because Dianna and Ryan Murphy(the showrunner) have never gotten along.
Sadly though it pissed me off that the Beatles got two episodes (the previous two) and Finn got one. When Cory died during the summer while they were still writing they should have condensed the Beatles episodes into one and had a two hour Finn tribute.
Blaine, Sam, Artie, and Ryder all have had close relationships to Finn (Blaine being his future brother in law, Sam living with the Hudson-Hummels, Artie being one of the reasons Finn was in ND, and Ryder was recruited to ND by Finn)
Granted none of the other new kids said anything but those four were the most glaring.
This post was edited on 10/10 at 9:25 pm