Go for plasma. Plasma has an overall better image, it´s cheaper and for gaming has a much better response time, 0,001 ms against 5 ms.
Burn in problems only happens with static images viewed hours and hours and it can be fixed. The only problem with plasma is more electricity consume.
I´ve got a Panasonic 42 PZ 80e bought a year ago and it has a great picture, even in SD images.
Top range lcd´s, like Sony KDL 40 Z5500, are clearly lower than a regular plasma.









