Plasma isn't as good as it's made out to be, I perfer LCD. First of all, Plasma will get dimmer and dimmer rather quickly, where as LCD will always stay the same. I think now is a bad time to get a high end TV, with SED just around the corner. It is cheaper than LCD and plasma, and it combines all the good qualities of CRT, LCD and Plasma.
(and holy
****, a 70" TV?? If it's LCD or plasma, that will cost more than some fancy cars! I know samsung makes an 80" plasma (they used to anyway) that cost $40,000.)