The Mother of All Fears
I've been very impressed with the Sony KDL-52XBR5, and it's rated #1 by most publications. But I'm afraid that after I buy it, Sony or some other company will come out with a newer, better TV with more features. When you attended CES, did you see any TVs that are better than the XBR5 and due to be released this year? I've heard some good things about the LG Opus LCD TV. I generally prefer LCDs over plasmas because of the lack of glare and burn-in issues. Which LCD has the best 120Hz feature?
Your concern about the next generation upstaging current models is very common but, I think, misguided. Manufacturers are always going to introduce new models every year with new features, better performance, etc. But if you keep waiting for the next model, you'll never get anything and miss out on the great images that today's best displays can produce. The TV you buy today will continue to look just as good in the future, even when newer, perhaps better models appear, so I say don't worry about what's coming down the pike—if you're ready to buy now, get the best you can afford from among the models that are currently available.
One caveat: if the set you want is at the end of its life cycle, it might be prudent to wait until the next generation becomes available; this usually occurs in the summer or fall. On the other hand, that might be the best time to find great deals on the outgoing models, much as it is with car shopping. Again, even if the next generation is better, that doesn't mean the current generation is suddenly crap.
I agree that the Sony XBR5 models (and the essentially identical XBR4s) are superb LCD TVs; see our review of the KDL-46XBR4. I haven't had a chance to look at the LG Opus line in any sort of critical environment, so I can't say how it compares with the XBR4/5 line at this point. I'm expecting to get one soon, so look for a review in a few weeks.
At CES, I didn't see any LCD TVs that best the Sonys in any significant way, at least among models that will be shipping this year. (Then again, the show floor is hardly an ideal environment to judge the picture quality of any TV.) There were many "concept" panels that looked fantastic—and were a fraction of an inch thick—but they won't be available for a couple of years at least. Interestingly, this is another parallel with the car industry.
In general, I find the 120Hz feature to be subtle with real-world material; it's more noticeable with certain types of moving test patterns. Sony's implementation of 120Hz works very well at smoothing out difficult scenes such as the pan across the village that opens Star Trek: Insurrection. Several colleagues complain that 120Hz changes the "look" of the picture, giving it an unnatural appearance, but I haven't noticed this among the 120Hz sets I've reviewed.
Bottom line: I'm convinced that you won't be disappointed with the Sony KDL-52XBR5 or 52XBR4. They're relatively expensive, but if you've got the scratch, they satisfy the high-def itch very effectively.