Well, Bezos has taken the full plunge now. The company agreed to spend $13.7 billion to buy the grocery store chain Whole Foods Market Inc., which has more than 450 stores, mostly in the United States. Until Friday's announcement, Amazon's largest acquisition was the $1.1 billion it agreed to pay for shoe seller Zappos in 2009. Amazon has so far controlled a tiny fraction of market share in America's highly fragmented grocery business. It's safe to say Bezos is using Whole Foods to speed up his ambitions to shake up food shopping -- one of the last areas relatively untouched by e-commerce. Without question, Amazon is the most interesting and ambitious company in the tech industry right now. Buying Whole Foods turns up the ambition dial even more. Bloomberg News had reported that Amazon looked at Whole Foods last fall but didn't pursue a deal. Since then, Whole Foods has been under investor pressure to reform a struggling business or sell.