I finally got mine yesterday.
Check your copies though.
Disc 1 - 2 very short scratches
Disc 2 - no scratch
Disc 3 - no scratch
I started watching the Extended Collector's Cut last night and finished its segment on disc 1. I'll be watching more on disc 2 today.
Picture quality is very good for me, comparable with that of the previous DVD release. Still I'm trying to find any noticeable change in picture quality.
As for the added cut scenes, they somewhat affect the pacing but at the very least they show more of James Cameron's vision and concepts. I find them enlightening to watch and I can hardly wait to see more later.