In response to the guys saying they're not getting the "pop" out of the picture they had hoped, I can understand what you mean. My old plasma definitely lacked it. When I went to my Samsung LED I felt I was seeing HD for the first time. The S64 is a good TV, but I like the LED I'm coming from, so I have been very critical of the S64. I've come around to liking it a lot though. For one, it's a 65" TV compared to the 46" LED. That's a huge difference. Second, I plugged in Cnet's settings on Cinema and D-Nice's settings on Custom and I've been rather happy since. I prefer D-Nice's settings even though the picture doesn't "pop" with brightness, it looks accurate. I see shadow details and the settings are great for daytime or nighttime viewing. Having said that, I'll probably try shenaniganz08's settings because I am an animation buff, which his settings favor, and I will probably check out Moshock's settings too since he claims his are the sweet spot for anytime viewing. So start with some settings and tweak them until you are happy. As someone said, it doesn't matter if you have a perfectly calibrated set if you find the picture isn't pleasing to you. We get so hung up on perfection that we can't be satisfied and happy. I'm one of them.
Adjust the set to your liking. In the end, if you aren't happy, return it if you can. But try adjusting settings to get that punch from it, if you can. I don't know how long you've spent adjusting it, but give it some time. Heck, I've even spent hours watching content on it, then switching the HDMI cable to my LED and watching the scenes to compare. At times I think, I'll just box it up and take it back. Then I watch it more and convince myself that I will keep it, and I've only had mine over a couple of weeks.
I don't like the line bleeding, and I do wish that whites got brighter, but I also noticed, even in the store, that the white of the LEDs was so high it obscured detail. Sometimes the white has a texture to it that I wasn't able to see with white being so intense. Honestly, I am still deciding whether to keep my S64 too. I am growing more attached to it though. Movies on Blu-ray, and even Netflix, look very good, IMO. I do not like having to deal with the light bleeding/flashligthing that occurs with so many LEDs. You also have the issue with motion and uniformity