American Express' (AXP) latest venture, in which it's supporting payments made through Twitter's platform, validates a concept that was in desperate need of it - social media commerce.
Up until the New York credit card company announced Monday it will allow its cardholders to purchase real-world items over the social media platform, there was doubt that Twitter transactions would ever get off the ground. "Amex definitely legitimizes it," says Rakesh Agrawal, a consultant on mobile payments and marketing. "They are a major....