BBC America is running a TNG marathon right now, and while the Standard Def (4x3) version is showing up fullscreen on my old 4x3 TV, the High Def BBCA channel is WEIRD.
They've got it cropped at the top (possibly the bottom too) and there's black bars on the left and right as well, but it certainly doesn't look the way you'd expect a 4x3 show to look on a widescreen channel, even the way a widescreen channel looks on a 4x3 set.
I checked the other room where I have a High Def widescreen TV.
On that, the widescreen/HD version of BBCA obviously has cropped the top (and bottom) off the picture. The black bars on the sides aren't as wide as on the Standard Def channel.
Kind of nasty that (on the widescreen channel) they'd cut off portions of the picture to supposedly make it fit better on a widescreen TV. Sure it's filling more of the wide screen, but it's also pushing portions off on the top and bottom.
Not respectful to the original material.
At least it's not the way TNN used to run the show, tho'. (Squashed from top to bottom so they could fit a big station ID banner at the bottom of the screen.)