Nielsen

Zappos founder Tony Hsieh's famous obsession with customer service paid off this holiday season. The Amazon-owned online shoe emporium came out on top in a Christmas delivery stress test performed by StellaService, a Nielsen-like ratings firm for internet shopping. StellaService's team of mystery shoppers set out to see which of the top online retailers met their promise of getting gifts under Christmas trees as long as orders were placed by their cut-off date.