I recently bought a Plasma and this what found out when I was doing my research. Plasmas have better black tones than LCDs. Only the best LCDs such as Sony can match them. Plasmas tend to dominate the market above 40 inch because the technology makes it nearly impossible to make them smaller. Plasmas consume more energy and if you have a big one (50 inch+) in a small room you will actually feel the room get warm. The gold standard for Plasmas is Pioneer, followed closely by Panansonic. All flat screen TVs these days are HD, if there is one out there for sale that isn't it's a relic. Every flat screen has two main components, the panel and the processor, it's the processor that really determines quality. The lower the quality of processor, the worse it will look with a standard defn signal. At the 42 inch size you do not need 1080P, you would barely notice the difference in picture quality, above that you start to see it. Plasmas are heavier than LCDs, a 42 inch will weigh 70 to 80 lbs. I do not know much about the Hitachis, I bought a Panasonic.
