Just to reiterate a bit based on my findings and experiences. Plasma has a reflective screen which I find distracting in all but pitch black rooms. Plasmas also don't appear all that sharp and crisp to me due to the pixels not being filled completely. It's hard to describe, but look at a plasma from about 1' away and the pixels have rounded off corners or something where there is a lot of black void space between each pixel. I don't see that on any of the other technologies except old analog tvs. For me, plasma was no good.
DLP and LCoS rear projection sets were two options where you can get excellent size for a low cost - main issue for me was the fact that you need to replace a bulb every few years at ~$300-$400 a bulb. I didn't care for the idea of
having to perform preventative maintenanve on my HDTV. Between the two technologies, I found LCoS (Sony SXRD or JVC HDiLA) to give the better picture - sharper and crisper with more vivid colors and no graininess or blur issues.
LCD won out for me due to color vividness, detail/sharpness, non reflective screen, long lifetime, and just a general "pop" to the image that I like. In my opinion, nowadays, you can't really go wrong with most LCDs out there - response time, inputs, processing, etc. are all good on most sets. The lesser known brands like Vizio and Westinghouse are extrememly competitive with the major brands like Sony and Samsung for a fraction of the cost. The main thing you need to observe for yourself with LCDs is contrast or black level, as that is the one area where they still have a little work to do. Websites like
www.hometheatermag.com measure the contrast ratio of LCD displays for you and that can be VERY helpful so you know what to expect in your room, but you still need to go to the store and compare them imo. The other thing to research is overscan, or how many pixels on a claimed 1080p display are cut off. The goal is to have all 1920 x 1080 pixels filled on a 1:1 ratio from the image source which would be no overscan. Some sets use processing to zoom in or cut off some pixels, meaning the whole image is slightly stretched. Some of the bigger brands like Samsung have a bad history of high overscan.