Capcom released a ton of Street Fighter IV videos at TGS 08, so I compiled them all (thanks GameTrailers.com) into one place. Below are the official Street Fighter IV TGS trailer, Meet and Greets with Sakura and Akuma and some gameplay footage from those two plus Dhalsim:

Street Fighter IV Official TGS Trailer
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Street Fighter IV: Meet Sakura
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Street Fighter IV: Meet Akuma
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Street Fighter IV: Sakura Gameplay (cam)
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Street Fighter IV: Akuma Gameplay (cam)
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Street Fighter IV: Sakura vs. Dhalsim Gameplay (cam)
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