...and DVD's (my primary visual sources, I will admit).
I don't have a whole lot of experience with 720p, I actually have more experience with 720p upscaled to 1080p (or higher -- but actually, didn't like the higher, which just means that I prefer the upscaler built into the Oppo than I did the one built into my Dell 30" 1600p screen. Which of course makes sense. That said, my statement was about 720p, not 720p upscaled to 1080p. I haven't liked any 720p large screen tv I've seen in any store, even correcting for difference. Heck, I can tell that they change the scale between the time-filler material they project on the screen in theaters digitally, and when they switch to the trailers.
I'll be honest -- I sit pretty close to my screen at home -- maybe 4 feet. 30", but I have it set so that it doesn't upscale, so 1080p only takes up 1080/1600 of it (vertically, and whatever the corresponding equivalent horizontally).
At Hirsch's, I sit maybe 10-15 feet away from his...52"? 1080p Panny Plasma.
At Dave's, I sit maybe 20-25 feet away from his screen which is...I don't know, huge (4'? ~half the wall high), 1080p, upscaled by...uh...I don't know, now that I think about it...projected by a JVC D-ILA something projector.
But I'll agree with that last statement about future-proofing and niggling-doubt -- If you can, get it for the psychology of getting it. If you really don't think you can tell the difference, then by all means, stop looking, and brainwash yourself into not seeing it, and get the 720p set. You'll only convince yourself you can see the difference, given enough time. Whether or not you can really tell the difference.