True enough like stated above if you don't have an HD display now you will definitely be missing out while you wait.
Plasma seems to be the state of the art today for overall picture quality in a large screen although screens are continuing to get larger. Later this year there will be a lot more screens over 50" from which to choose.
Until late last year plasmas were 768p. A jump to the next resolution is underway and by end of this year there will be a number of 1080p displays to join the few that came out last year. This is a substantial increase in resolution but useful mainly in large displays 60" and up and when sitting fairly close.
The next big thing on the horizon looks like OLED. Another possibility is SED but it is having its problems. OLED today is available in very small displays and Sony I believe will offer a 27". There is a lot of R&D directed toward this worldwide. I don't know what the projected timeframe is for large screen commercialization. Either one of these technologies may prove to displace current technology from a quality standpoint. With plasma's quality advantage coupled with its smaller footprint and declining prices, I see RPTV as currently viable but temporary.
The sweet spot in plasma pricing today is at 50. Later this year will see a larger volume and variety of 60+ displays and a choice of 1080p as well. Although prices will continue to fall, these should remain somewhat pricey this year. Next year will see I think larger declines in prices of large screen plasmas like this past year saw on 50 displays.
In an associated technology, advanced video processing chips are emerging in players and soon receivers that will markedly increase the quality of video signals sent to these displays. This is due to professional Teranax algorithms previously used only in Hollywood post productions studios trickling down into consumer products via integrated tera-flop processing chips such as Silicon Optics Realta and lite-version Reon chips.
HDMI ver 1.3 connectivity should finally be here in 2007 to provide a stable and standard interface for high resolution content.
So sure in 18 months larger 1080p plasma displays along with advanced processing chips in high-def sources and standard interfaces to carry the signals all at lower prices brought on by an explosion of world wide volume should make purchasing fun. And by that time there should be a lot more high-def material. D*TV, for instance, is bringing on-line this year several high-def birds that will greatly expand their offerings.
Now if we could only get some content worth watching in high def and if the producers of that content would make an effort in the direction of picture quality we would all be better off.