The following video is part of our "Motley Fool Conversations" series, in which Katrina Chan and Greg Robleto discuss topics across the investing world.

American Express has entered into a new exclusive partnership with the social media site Twitter to provide a fresh new means of offering users discounts for using their AmEx card and Tweeting about their purchases. Greg and Katrina look at this arrangement from all angles, examining how it will benefit AmEx,Twitter, the retail partners, and the end users.

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