I've just finished a first pass at conforming the Blu-ray to the cut present on the Laserdisc (using the Angrysun edition). The color grade has, of course, been extremely altered and several scenes were rearranged, but other than THX's initial meeting with SEN and the factory sequences I didn't find much that was completely re-edited.
There's the movie-censorship article which cites most of the alterations so I'm only giving additional observations:
-Two out of three of the SEN shots removed from the opening were found later on the Blu-ray with no missing or modified frames (the first extreme close-up is gone).
-The opening "grid" shot, which was modified with monitor/scanlines, is pulled from a clean shot before the trial, meaning it can be re-created.
-From the trial sequence up until the escape to the crowded mass the two edits are almost completely identical. *Almost* because I spotted missing frames on the Angrysun version (no idea how that happened), two missing frames from the Blu-ray, and only one digital alteration when THX and SEN walk off into the horizon (the food squares SEN drops don't fade to white on the Blu-ray).
-Most of the horizontally flipped shots were spotted except a couple during the white prison escape. I only noticed one digital alteration that wasn't spotted (unless it's Blu-ray only): the bird's-eye view shot of the officers at 1:04:06 (Angrysun timecode) has an added foreground that resembles looking down a manhole cover.
Quantified in minutes, starting after the opening credits
72:12:47 of the film exists intact on the Blu-ray
9:51:13 has been modified, including shots with missing frames
2:36:12 has been removed entirely
I've begun rotoscoping (a la Harmy) on some of the simpler shots and noticed the LD transfer doesn't fit the Blu-ray 1:1, which I'm pretty sure is because the LD was pulled from an anamorphic print while the Blu-ray/DVD was directly from a Techniscope element (if not the negative)-- your pesky white speck in the last third could be something that got sucked into the optical printer during the blow-up process. Is there a simple way to rectify anamorphic distortion?
(Software I am using is Adobe Premiere and After Effects CS4)
As some of these shots only modify a small part of the frame, I'd find the pan-and-scan versions to be useful to work with. Are there any seeders for the Italian cut (or any other pan-and-scan version)?