Okay I've been reading these posts and I have a few things to say.
1) To the guy that has spacers between his set and the wall mounting bracket, TAKE THEM OFF but make sure not to use the same size screw. The sequence is: Screw, lock washer, flat washer, bracket, TV. (If you have a 58" or 63" set and you are using a wall mount, remember to remove the small black screws that are around the mounting points so that the bracket can lay flush against the back of the set. All these screws do is help secure the rear cover panel. Once the brackets are on, they'll do a better job of holding on the rear panel than those tiny screws.) You can use a thin strip of black vinyl tape along the surface of the set or better yet, on the bracket surface if you don't wish any scratches on your TV.
2) Buzzing sets do appear to be a USA issue. It's starting to look as if it has something to do with transforming our 120Voltage system as apposed to Europe's 220V system to power up those plasma cells, or possibly old wiring in ones home, fl. lights & ballast proximity to the set or on the same line, and/or stress during shipping. (Invest in a line filter, it may help.)
3) However, our USA 63" C8000 set is PERFECT without as much as a PEEP. I have it suspended (floating) in mid air within a well ventilated opening (it's huge this opening) within the wall of the family room... our Dish Network HD DVR makes more noise than my fridge. (POS it is.)
4) For some reason, Mantis' calibrations didn't totally work for me but I'm glad he posted them, they were a great starting point. My crew and I have been tweeking his settings for the last few hours and we're almost there. We're now using the same color analyzer as he but we're coming up with different settings. First off, this Plasma is good, but not as good as some earlier Sammy's IMO, and by far not as pure as our old and now sadly kaput KURO. This Sammy (at least my set) has a tough time producing pure clean whites, and smooth even blacks. (My guys are telling me it's the new 3D video processor.... it can't/doesn't produce super deep blacks.)
5) A word of caution. On the larger sets (58-63) the base is held on and mounted to this 85lb set with only a few super small & wimpy screws.... we couldn't believe it... !
6) Although the 3D processing is great and all, it defeats the true value of 1080p in my opinion.... it makes the image we cinematographers work so hard to produce a little too soft for my taste.... unless perfected, a fading fad I hope.