I don't believe the 750 really "replaces" the 550 and 650 series. They are simply different higher/lower-end models. The 550 and 650 models, which are both still being sold at retail stores and all over the internet, are probably the two most popular Samsung TVs right now. But who am i to say. Seksiexboy is the one working at the best buy, so take my words with a grain of salt.
Discontinued or not, if you're in the market for a 2008 Samsung LCD TV model anytime soon, it is safe to say that it will most likely be a choice between the 550 or 650 series. There are many differences between the two series. Some, such as higher contrast ratios are pretty much negligible to the average eye. The main "benefit" you get from choosing the 650 over the 550 is the 120hz refresh rate.
There is a lot of confusion and misconception about what 120hz actually does. While some see it as a gimmick which is not worth the price difference, some see it as the next big thing in home entertainment. I'm no expert, but I could break down what 120hz is in layman terms if anybody is interested. I've been doing a lot of research on the technology since it will be the deciding factor on whether I get the 550 or 650 model. (Yes, I'm going to choose one of the two
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