I have its kid brother (or sister) 42HDS69 and it's simply awesome! I've seen the 55" at the store and it's the same. My 42" gives a superb picture especially on digital DVDs (new Star Wars trilogy)or high quality film movies (last 4 Star Trek movies). I now find myself sitting 3 to 4 feet in front of it so that I can see all the details on digital movies especially, as opposed to 18' with the old 36" tube. Satellite TV is excellent also, and I'm not even talking of HD sources yet! We got a new Yamaha DVD surround sound system a few months ago, so I'm not about to upgrade that yet. But considering the very high picture quality, I'm in no rush. If you can afford it, then get it. I passed it up due to the $$$.
I was just reading online about the Hitachi 55HDS69, and I've come away impressed. Does anyone have one, or have any information about this set?