This has come up a couple times at GolfWRX. I've kinda got a thing for TVs, almost as bad as my thing for clubs.
I'll copy/paste exactly what I said there:
First off, do your homework. Start reading now.
Secondly, how big do you want to go? More importantly, what is your screen viewing distance now?
Thirdly, after you've read and read (... and read) about the differences in the type of technology, you'll need to decide on what your needs are and how they fit into your budget. Between projection (DLP, LCoS), LCD, and plasma.. try not to get overwhelmed.
Don't get all turned up about 1080p, unless you have a hi-def media player... you won't reap the actual benefits for at least a couple more years (nobody broadcasts in 1080p yet).
If you wanna go big (we all do!) and keep it under $2k, you might look into a projection-tech tv. Whether it's DLP or LCoS (Sony's SXRD) you can't really go wrong with either. You get your most bang for the buck and can easily find a nice 56" HDTV for sub-$2000. With price matching and shopping around, I wouldn't be surprised if you could find a 65" for around the same price.
If you want something thin (like a wallhanger) and are looking at a set smaller than 50", LCDs and Plasmas are probably right up your alley.
I could go on and on, but I'll let you do the research... you'll learn more that way and be able to make an informed decision.
Last but not least... shop around! Check your Sunday ads and visit some of your local retailers. Make them price match and you'll save a ton. Don't let them rope you in on some cheesy warranty either.