I've learned my lesson on this subject. If you can get an extended warranty at a decent price, then go for it. I personally buy nothing but big names when it comes to a purchase that much $$ and ALWAYS get the extended warranty REGARDLESS. Circuit City is great. Their customer service is awesome and the warranty can always be purchased or extended later.
Just do your research. For example, Samsung Plasma's suck, but their LCD's rock. I bought a 50" Samsung Plasma before the LCD's got bigger/cheaper (about 2 years ago) and it quit working sporadically. After some research and one call to Circuit city I had a new DLP with no questions asked. My Mitsu DLP (1080p) makes my Samsung look stupid. Panasonic makes some great LCD's as well. Call Circuit City and ask to talk to a field tech, he will know best. I think the guys name is Sam or something, some old man, he knows his shit.