Alibaba overtakes Amazon as most highly valued U.S. online retailer

Amazon now has a global rival for both consumer and investor dollars: Alibaba. The company went public in the U.S. market yesterday at a record $68 a share. Alibaba's valuation is now at $167.6 billion, above Amazon's $150.2 billion. It seems the once dominant e-commerce player may have to watch its back. Story