I don't know if you're dead-set on a plasma. If not....
About a month ago I made the jump into the HDTV world. I had a nice Toshiba 36" SDTV and went to a Samsung 61" LED DLP ( HL61A750
). Full 1080p. It was $1,700 from Amazon, no tax & free to-my-livingroom-shipping.
I had done an incredible amount of comparison shopping in the past few years, and this set finally hit the mark for me as far as performance (HD & SD) and price. I didn't want to hang the TV on the wall so I spent hours comparing DLP vs LCD vs Plasma.
I am 100% happy with the decision on this set. It's absolutely fantastic. The LED light source should last basically forever (20k hours), and no spinning color wheel means that there is zero noise and no 'screen door' effect. I do not yet own any 1080p sources, but both 720p and 1080i HD (OTA & Dish) looks incredible. It even does a fairly good job on the few channels that I watch in SD, which is surprising.
It is true that this is my first HD set, and thus I don't have a lot of personal experience to draw from. But I know what I've seen comparing this to other models at the store, and from watching HDTV at friends' homes. It seems to be a really good set at a very good price. Just so long as it's not a requirement to be wall-mountable.