LEDs are LCDs.
The difference is what they use for backlight: Regular LCDs have fluorescent backlights, LED LCDs have, well, LED backlights. They can lead to better dynamic ranges because of better local dimming, but if you look at the light emitted from the set it's often very blue. Not a reason not to pick one up, just a note.
Agreed: Plasmas run warmer than LCDs.
Whatever you decide upon, calibrate it whenever you get it into position for best performance.