- i think they only go up to 40in (anything higher than that will be really expensive!)
- better overall picture in my opinion
- longer lasting
- problems displaying a 'true' black
- Cheaper at larger sizes (80" is the largest i have seen in person)
- burnout problems (apparently this is less of an issue now, however how much you can trust the companies that are trying to sell you a £4000 TV when they tell you this is unknown!)
- older tech
I went with a 40in LCD by Sony, and have absolutely no problems with it, it's picture was the best to my eyes, and i was never going to buy plasma because of the burnout problems!
My best advice, be aware of the limitations of both types (burnout/difficulty in displaying 'black') and check them out with your own eyes, pick what you think looks best!