LCD's. Asked the guy at the store when i bought it which one is better for gaming. He did say Plasma's screen's burn, and there is a huge reflection from the sun and lights. LCD's have very little reflection and don't burn, they are actually made for gaming as well as normal TV.
Thy are cheaper than large LCDs, have higher brightness and contrast and higher refresh-rate (0,001ms instead 2ms like LCDs). Modern plasma displays don't have the burn-in problem anymore. The average use of power of modern plasma displays is the same (and sometimes less) than LCD (only good LED TVs have a lower use of power).