Davehead, my HD Phillips is 4:3. The only letter-boxing that goes on is for widescreen DVDs.
My TV was relatively cheap and IMO provides a huge and beautiful picture w/ 480p images. It even does a good job upgrading the std cable signal to acceptable quality.
Nobody seems to agree w/ me, but based on my experience I would recommend big, cheap, 4:3, HD (1080), CRT RPTV. Couldn't be happier (w/ PQ - the TV itself is kinda ugly).