Regarding Plasma TVs; Panasonic was the absolute king of the hill until Pioneer dethroned them. Still very high quality.
(Keep in mind Pioneer will no longer make their own plasma panels. Who will supply them? Panasonic)
However, Samsung has been in the LCD business longer by virtue of their presence in the PC monitor arena.
(Pioneer will offer LCDs for the first time and the LCD panels will be made by....Sharp)
IMO, you can't go wrong with either as they are both "top tier" brands. Remember the best judge of a TVs performance is your eyes (and ears). Nothing will beat viewing each set in person and using the same source for the picture. Keep in mind though that many sets must be adjusted for the absolute best picture.
After comparing Pic and sound quality take into consideration the warranty, build quality, remote ergonomics/performance and features such as HDMI and DVI inputs. AND the Return Policy...Think Costco or Walmart who are quite liberal.
Tip: If you have an American Express card then use it and get a 1 year warranty extension automatically. This may only work with Amex Gold or higher so check first.
No question, the best place to do online research on TV performance and specifications is CNET.
Another consideration is using a feedback site such as Epinions to see what owners of a component have to say regarding there experience.
Also check out how Consumer Reports rated LCDs using many factors. Takes a few moments to load.
Check out the links below and good luck.
*** And check out Vizio as well

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