First off, you would be much better off doing your research on a home theater forum than a computer forum. In my opinion, the best place to do this is AVS forum:
http://www.avsforum.com/avs-vb/
I did quite a bit of research last year on TVs, considering both LCD and plasma. Here are a few random comments/responses:
1. Regarding LCD manufacturers, LG is not generally held in high regard on the HT sites I've gone to. Far and away the top two brands among HT people are Sony and Samsung. For years, Sony has had the reputation as the best, but a lot of people feel that Samsung has equaled or surpassed Sony. Toshiba sometimes get mentioned as being in the same class, though appears to be harder to find. Sony's are far more expensive, which helps a lot of people choose Samsung.
2. A lot of people claim that burn-in/image retention isn't a problem on plasma sets anymore. However, it is still a huge topic of conversation on the AVS Forum plasma page. If you plan to do a lot of gaming, I would spend some serious time over at AVS Forum researching it and then draw your own conclusions. As someone who watches a lot of 4:3 material, I finally convinced myself that plasma wasnt for me (they kept recommending stretching the image to fill the screen, which I won't do; and why should I need to stretch it if burn-in isn't a problem? Hmm...).
3. If I were going to get a plasma, I would seriously consider the Samsungs. From my research, I got the impression that Pioneer was the best and Panasonic was second best, and no one else was close. However, Pioneer is out of the business and a lot of people seem to think that the recent Samsung models can now compete with the Panasonics. Do your research.
4. Do you need a thin, hang-on-the-wall kind of TV? If not, it might be worth considering DLP sets (which is what I finally decided on). Yes, it is a dying technology (Mitsubishi is the only manufacturer left in the business), but it offers a great picture for a very reasonable price. They may be deeper than LCD or plasma sets, but theyre actually as light or lighter (for the screen size). If you want a really big set (I dont think they even make DLP sets under 60 any more), you cant beat DLP. Check out this unit:
http://www.amazon.com/Mitsubishi-WD...ref=sr_1_1?ie=UTF8&s=tv&qid=1255098981&sr=1-1
Once again, you would be much better off spending some serious time over at AVS Forum than getting opinions from people on a computer forum. The people who obsess over this stuff are hanging out over there. The sheer amount of information will be overwhelming at first. However, if you put in the time and learn to sift through the chaff, youll be in a much better position to make an informed decision.