Hi Ben!
Okay, for some reason, we seem to have got off on the wrong foot. My post was designed to be helpful to a new comer to the forums. Basically, I'm not a technical person, so I can't give you the exact technical reasons why what I say is true. However, I do know, that in order to display a native 1080p output, a screen must have at least 1080 vertical lines i.e. in general this means the resolution of the TV is 1920 x 1080 (or more) and is termed a "Full HD" set or "HD Ready 1080p" set.
1080i is different. I know the "i" stands for interlaced and this means that the TV updates every other line every 50th / 60th of a second (depending on the frequency of the signal / television you are watching). Then it updates the line it didn't update last time a 50th / 60th of a second later. In this way, a picture is produced and, because of the human eye's limitations, we barely notice this (if we notice it at all). With the "p", (which stands for progressive) every line is updated every 50th / 60th of a second, in theory giving a smoother picture (I say in theory due to the human eye's limitations, therefore, not everyone would actually be able to see the difference. Generally, the bigger the set, the more noticeable it is, which makes sense).
Now this is where my technical knowledge gets hazy, but my practical knowledge stands up and shows my original answer to be correct. I know my Panasonic television has a resolution of 1024x768 i.e. the same as the two televisions the man / woman posted about. I also know from use, that my television is natively compatible to display 720p and 1080i signals, but cannot natively display 1080p signals and has to descale them to one of the other formats. Having done a little research on the TVs the original poster asked about, I was then able to tell him they did the same.
Personally, I don't know why this is the case (though I can guess it has something to do with the image being interlaced rather than progressive), but I can tell you it's true. Therefore, the two televisions he was asking advice on can natively output 720p or 1080i signals, but cannot output 1080p signals.
Now, I'm never a man to not admit I'm wrong if proved otherwise, so if you know different, please explain this rather than just saying I'm wrong and not giving any evidence to show this!
I hope this clears this all up, and if I am wrong, I'm happy to be educated and also for the poster to be shown the correct information too. As I say... I was only trying to help!