I've learned a few things in my research. First, auditioning is of limited value. I've gone to a few local big box stores and the TV's are adjusted so poorly and so differently, that you cannot really get a sense for how they will look when they are properly calibrated. Some were so badly set up that I can only imagine that the stores were deliberately doing it that way to convince you to buy a different brand.
We don't have any high end stores around here anymore, so that wasn't an option. I prefer to order online anyway, so I wouldn't want to take up a paid salesman's time. Eons and eons ago, you could find good salesman at stores like this and they would add sufficient value to the proposition to make buying from them sensible. Now, the low prices online and the migration of knowledgeable salesmen to the custom installation world seem to have wiped out good high end stores. My guess is that they still exist in the right markets, but we don't appear to have one up here in suburbs.
3D looks interesting. I can't see myself putting on special glasses to watch a movie or sporting event very often. The effect works better with the active shutter glasses compared with the polarized glasses at theaters. I have no clue whether it will survive in the marketplace. I'm digging around now to see if I can take 3D photos and encode them to be viewed in 3D. That would be fun. If anyone has any leads on how to do this, I'd love to hear them.
I suspect that 3D will really take off with the next generation of game consoles. It should be easy to make 3D video games since they are all 3D already and just rendered in 2D. Most video games have fewer people in the audience than movies, so there won't be a need to buy insanely expensive (over $100 each) glasses.
I'm still on the fence between plasma and LCD-LED. I'm leaning towards plasma at this point because it is so much cheaper. While I can understand llrain's reluctance to buy another plasma after having been burned, my research didn't turn up any indicators that one or the other was more reliable. It looks like LCD will last longer, but we're talking about lifespans for 15 years vs 30 years or other excessive stuff like that. I'm working under the assumption that I'll get 5 years of primary use out of this TV and 5 more years of secondary use (guest room or something).
I was a bit concerned by recommendations (here and elsewhere) against using a plasma for a computer screen, but VVFF cleared that up nicely.
As for source material, I'll be playing a fairly standard mix of Blu-rays, DVDs, computer video files, satellite TV, and game system games. We already have a Wii connected via component cables to a 50" 720p TV, so I don't expect it to look much different. I expect the Xbox 360 and PS3 to look better, but at this point my kids almost never use those devices, so I don't really care. The areas where I'm expecting the biggest improvements are displaying our photographs and Blu-ray movies.
At the moment, I'm leaning towards the Samsung PN50C8000 or PN50C7000. Those are their 50" plasmas. It's not clear that they are really different in terms of hardware and there appears to be a firmware "hack" to convert a C7000 into a C8000. It's the perfect size for our shelf. If I went with their LCD-LED, I'd either need a smaller screen or I'd have to do some rework to make it fit well.
I think that my next step will be to line up someone to do the calibration and get their opinion on the sets. Any idea on the best way to find someone that does calibration?