Got my 552 yesterday!!! 
The box is HUGE. And the TV itself is larger than I thought. I have an existing TV wall mount installed so I used it. I didn't account for the speaker at the bottom of the TV so its sitting about 1/2" off the top of the fireplace mantle. I'm going to purchase the motorized mount in a few weeks and reinstall it higher. I've got Comcast HD cable and a PS3 connected along with my Argosy HDD Media Device. I'm using it to play mp4 files from my PS3 or I can connect it directly via HDMI and watch other file formats directly from it. Here's some pics. I'm getting a media center tomorrow so I'll post some video of the TV in action.