I got the XBR55X700D last week and finally got around to setting it up and trying a few video sources. Looks good so far.
For a while I thought there might be a video size issue as most of my Blu Ray movies and many Netflix movies play with a small black bar at the top and bottom. I never noticed that before due to using smaller displays that also might have some zooming enabled. I researched the problematic movie titles and found that my older movies (Taxi Driver, The Terminator, The Killer) were released with 1.85 aspect ratio. 1080P or 16x9 is ratio 1.77.
Blu-rays play smoothly but I have noticed some jerkiness on some streamed videos when they do a horizontal pan. This might be a TV issue, but I'm thinking it may be a slow Wi-fi connection. Wi-fi needs to go 20 feet through at least 2 walls. I will eventually run a cable so I can get the speed of a wired network connection.
Theater 1 (living room): 65" TV Sony XBR65X900F, Denon AVR-S720W receiver, speakers for 5.1: 6 Kef Q100 (dual center), Klipsch SW-110B 10" subwoofer.
Theater 2 (family room): 55" TV Sony XBR55X700D, Klipsch Promedia 2.1 speaker system.
Video sources: Telus 1080i PVR, Apple TV 3 (Netflix, YT), Sony 1080P BR player