Plasma and LCD aren't too far apart when properly calibrated. If you want them in torch mode as if they were competing with a retail stores bright lighting, then sure.. plasma will use more energy than LCDs.
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Regarding movement, content is going to be 24 or 30 fps. LCDs are trying to bandaid poor motion performance by artificially creating frames that don't exist in the source. While this does help to alleviate blur that is the result of sample and hold, it also serves to introduce motion artifacts that many find bothersome or unacceptable.
A plasma uses more power than an LCD in equivalent size http://reviews.cnet.com/green-tech/tv-consumption-chart/ - click on "Calibrated Settings" then "Screen Size" to sort lowest to highest power use after calibration by screen size and you will see that Plasmas feature predominantly at the bottom of every size category.
As for refresh rates, there is always the possibility that someday (preferably soon) that will be more media available that is at 60 interlaced frames per second, which requires a refresh rate of 120Hz I was told by a technician for a post-production company that animates at very high framerates to make motion look more real - something that apparently the PS3 already makes use of.
Unfortunately Hollywood et al likes 24Hz as it is the lowest number of frames they can get away with whilst still giving the impression of motion, thereby saving considerable production costs as you pay for film, then film processing and then digitizing (e.g. Telecine) by the foot. So to make a film with more realistic motion at 60Hz would require 2.5x (24x2.5=60) more film, and therefore 2.5x more film costs.