That article isn't really that useful. It doesn't test 1080p sources and say that the 1080p displays don't display them correctly.
It is testing 1080i sources and saying they don't convert back to 1080p perfectly. It is interesting to see that so many displays can't properly deinterlace, but no where in that article does it actually say 1080p is not 1080p. All it says is that some 1080p sets will have problems with 1080i.
