Will Amazon prove naysayers wrong - again?

A few years ago, the rap against Amazon.com Inc. (AMZN) was that it was a high-cost, low margin business facing fierce competition from the likes of Wal-Mart Stores Inc. (WMT) and eBay Inc. (EBAY). Now, these naysayers, including yours truly, are singing a different tune.

Analysts are expecting the Seattle-based company to post a year-over-year revenue gain of 15 percent to $4.76 billion, a remarkable achievement considering the precarious financial state of many traditional retailers. Earnings per share is expected to dip to 31 cents per share from 34 cent a year earlier. Estimates range from 26 to 38 cents, according to Thomson Reuters.

The e-commerce giant, which reports earnings after the close of trading today, has been on a tear lately, surging more than 54 percent this year as shoppers snapped up online bargains while avoiding traditional bricks-and-mortar stores. Amazon has successfully diversified beyond books and CDs into areas as diverse as digital media to jewelry. The strategy appears to be working.