Go with flat-panels and hang it on wall, won't loose the TV next time basement floods. With the prices so low these days for flat-panels, they make more sense. Or you can just get a nice projector. I am also in the market for >50" flat-panel.
Pioneer Pro1540HD and Panasonic TH-65PX600U are good in plasma. For LCD; Sharp Aquos LC-65D90U is good. Sony is out of plasma TV market and the biggest LCD they have on their site is 52". Samsung is other major vendor but not sure about their quality.