When I bought my TV I went to my local indy retailer with my wife and watched screens by Samsung, Lowe, Panasonic, Pioneer, Sony, Hitachi, B&O and Sharp. We watched the same freeview, DVD, Bluray, HDDVD and 1080p files though each of them.
Having done my research, read all the websites and reviews I knew that I wanted the Sony 40X3500 1080p LCD, but since it was £2000 I wanted my wife to make her own decision and see that this was obviously the superior panel.
After an hour playing with the settings an a number of the screens we thought were contenders it was clear we were wasting our time, one of the 720p plasmas had quite clearly wiped the floor with everything.
If you see a TV and you think it gives a better picture than all the others at the viewing distance you'll use it at then that's the TV for you.