Hey, anybody have a solution or "for sure" reason for this problem yet? I just started noticing the same thing on my Sceptre 37", but on the left side. I wouldn't call it black, but definitely darker. When on the Windows desktop (blue), you can see it as blue-gray. When watching superbowl, the field (green) you could sometimes see it as darker, even from several feet back. Other scenes (different colors) you can't notice it at all. Most people would not notice it unless they know what and where to look (kind of like that one blue pixel I have). But that pixel is too small to see from where I sit, the line however isn't and I'm worried it could get worse.
Mine doesn't seem to exactly line up with the 4:3 line though, but I think that can vary sometimes.
I notice when I power mine on (after being off overnight),you can't notice it right away but after a few minutes you can. I'm going to try running white screen overnight to see if it helps, but I think like a poster said above it will still be there. I took my first Sceptre back due to this same discoloration, but it was a in upper right and wasn't a distinct line, but more of irregular lines 4" long, rather than a uniform line more or less full vertical length. But the colors were exactly the same.
Mine seems very similar to picture above.
A good way to see this problem is put on a white screen and adjust contrast down.
It seems this may be on LCDs from different brands, so I'm kind of lost as to why there isn't a clearcut answer to this.