Well i have a 42" panasonic "Viera" HD Plasma (using a neo pdp screen, this makes it a lot cheaper to run), i prefer plasma as they produce better blacks and pverall picture definition than lcd tv's. They also have a better depth of picture. Plasma will last a lot longer too.
Watching sports on brothers 42" (it runs in the family

) sony lcd tv i notice picture blur when watching football, even the quickest response times on lcd's will have this to some degree, plasmas and the old CRT tv's have virtually a zero response time.
The bit below is from wikipedia:
Slim profile
Can be wall mounted
Lighter and less bulky than rear-projection televisions
Achieves better and more accurate color reproduction than LCDs (68 billion/236 versus 16.7 million/224)[6][3]
Produces deep, true blacks allowing for superior contrast ratios (up to 1:2,000,000)[6][3][7]
Far wider viewing angles than those of LCD (up to 178°); images do not suffer from degradation at high angles unlike LCDs[6][3]
Virtually no motion blur, thanks in large part to very high refresh rates and a faster response time, contributing to superior performance when displaying content with significant amounts of rapid motion.
I have 4 large lcd tv's and a plasma, the plasma is better.