I've got a Samsung something or other (it's the LE range I think). It's 37" and was (just) under £500 which was a big selling point. Other than that I did drive myself mental comparing dozens of different makes and models, it seems like whenever you get a concrete review stating Panasonic's the best option you'll then stumble on another one claiming another brand are better and vice versa. It was pretty maddening and in truth once you're going full-HD it's gonna look pretty awesome regardless.
Eventually I just plumped for the Samsung because it's what I had at work at the time and I'd been pretty impressed. Also, the Samsung's have "game mode" which skips a lot of the post-processing to get the image up quicker, thus eliminating a lot of the input latency. I have to say I've never noticed any lag myself with it on, nor have I noticed a significant difference in the picture quality with it off, so for gaming I'm very very happy. I'm sure you're going to get a lot of varied replies though!