It also depends on the TV. I have a Kuro 768p that will kill most 1080P LCD tv's. I have a Samsung 46 650 and my wife prefers the Kuro, so there is more criteria to consider than just numbers.
From Cnet:
9. Side by side, how do 720p and 1080p TVs match up in head-to-head tests?
We spend a lot of time looking at a variety of source material on a variety of TVs in our video lab here at CNET's offices in New York. When I wrote my original article over three years ago, many 1080p TVs weren't as sharp as they claimed to be on paper. By that, I mean a lot of older 1080p sets couldn't necessarily display all 2 million-plus pixels in the real world--technically, speaking, they couldn't "resolve" every line of a 1080i or 1080p test pattern.
That's changed in the last few years. Virtually all 1080p sets are now capable of fully resolving 1080i and 1080p material, though not every 1080p TV is created equal. As our resident video guru, Senior Editor David Katzmaier explains in his HDTV resolutions feature, Blu-ray serves up another video format, 1080p/24, and not every TV properly displays 1080p/24. The 24 refers to the true frame rate of film-based content, and displaying it in its native format is supposed to give you a picture exactly as the director intended you to see it (for a full explanation, click here).
Whether you're dealing with 1080p/24 or standard 1080p/60, doesn't alter our overall views about 1080p TVs. We still believe that when you're dealing with TVs 50 inches and smaller, the added resolution has only a very minor impact on picture quality.
In our tests, we put 720p (or 768p) sets next to 1080p sets, then feed them both the same source material, whether it's 1080i or 1080p, from the highest-quality Blu-ray player. We typically watch both sets for a while, with eyes darting back and forth between the two, looking for differences in the most-detailed sections, such as hair, textures of fabric, and grassy plains. Bottom line: It's almost always very difficult to see any difference--especially from farther than 8 feet away on a 50-inch TV.
I said so much in a 2006 column I wrote called "The case against 1080p," but some readers knocked us for not looking at high-end TVs in our tests. But the fact is, resolution is resolution, and whether you're looking at a Sony or a Westinghouse, 1080p resolution--which relates to picture sharpness--is the same and is a separate issue from black levels and color accuracy.
Katzmaier stands by his previous analysis: The extra sharpness afforded by the 1080p televisions he's seen is noticeable only when watching 1080i or 1080p sources on a larger screens, say 55 inches and bigger, or with projectors that display a wall-size picture. Katzmaier also says that the main real-world advantage of 1080p is not the extra sharpness you'll be seeing, but instead, the smaller, more densely packed pixels. In other words, you can sit closer to a 1080p television and not notice any pixel structure, such as stair-stepping along diagonal lines, or the screen-door effect (where you can actually see the space between the pixels). This advantage applies regardless of the quality of the source.
Link:
http://reviews.cnet.com/720p-vs-1080p-hdtv/
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Is this statement true?
and wants his 
. He needs some serious glasses.
Sometimes it's all a matter of perspective. I can DEFINITELY tell the difference big-time. If it looks better to you, that's all that matters, and then you can justify spending obscenely large amounts of money on it (like I do) 
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