Finally saw 3D on the 55C7000 at Best Buy. They had about 30 minutes from different parts of Monsters Vs Aliens, featuring scenes with Susan/Ginormica. I also saw 3D conversion on Pirates of the Carribean on Bluray. They had 1 pair of glasses wired to a desk by two chairs at a comfortable viewing distance. The had nothing in stock other than the display units but could order all components: TV, glasses, bluray player and receiver.
My overall impression was quite good at first, seeing 3D for the first time, although over animated images, hard to tell what a movie would look like. Switching to 2D, the C7000 had such an amazing picture quality it already looked 3D, much as on my 55B8000. The glasses did make it noticably darker and there was a noticble loss of picture quality in 3D, maybe due to 120Hz to each eye, not sure. Only a few scenes had real pop out 3D, such as when Susan held a gun on the alien towards the end, but most did not. That same scene under 2D also looked pretty 3D. It did not appear to have the same jaw-dropping effect as Avatar in Digital 3D, as much as I wanted to see it. I saw three icons for 3D selection, only one works with the 3D bluray, but didn't learn about any other potential 3D settings.
When playing a Pirates of the Carribean bluray disk under 3D on the TV, it was hard to tell if the 3D effect was even on, there was very little 3D effect if any. The associate assured me it was on.
They also had a 55B8500 on display playing Speed Racer and the brightness and contrast was impressive, although that movie is different from most.
Now watching Fast & Furious on HD cable on the 55B8000 and it's very 3D and with about as close to perfect pq as could be.
I'll wait for the 65C8000 and more movie content to evaluate. I wonder what might provide the same level of quality under 3D as today's 2D from Samsung, better 3D bluray disks? 480Hz? The c8000 series?