I'm not sure if there is a way to do it or not but it may be worth pointing out that the captivate screen doesn't have the resolution to display 720p. I have heard that the iPhone 4 packs a very large number of pixels so 720p probably makes sense on that phone. I have also heard that the pixels are so small that they may not be entirely decernible to the human eye.
I would be interested in knowing if you do find a way to view 720p on the captivate. I'm more interested in downloading than viewing though.
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