Barnes & Noble Inc. announced today that it has named BarnesandNoble.com president William Lynch as its new CEO. He replaces Steve Riggio who will remain vice chairman.

Lynch, who joined Barnes & Noble, No. 41 in the Internet Retailer Top 500 Guide, in February 2009, oversaw the company’s introduction of an e-book store, acquisition of e-book marketplace Fictionwise and launch of the nook e-book reader.

The shakeup comes as the company moves to transform itself from a conventional book retailer into a major e-commerce franchise by leveraging its burgeoning online business and aggressive push into the e-book reader market. “2009 was a year in which we set the stage for growth and we expect that 2010 will be a watershed year in Barnes & Noble`s transformation from being a brick-and-mortar retailer to becoming a major e-commerce retailer,” Riggio told analysts last month.

Lynch’s web retailing credentials apparently helped secure him the CEO spot. “William came to us as a skillful leader in e-commerce who, in a short period of time, has done a superb job in quickly establishing Barnes & Noble as a major player in e-commerce and digital content,” says Leonard Riggio, Barnes & Noble chairman and brother of Steve Riggio. “Given the dynamic nature of the book industry, William is uniquely qualified to lead the company`s transition to multichannel distribution and drive the continuing expansion of our e-commerce platform, eBooks and other digital content and products.”

Prior to joining Barnes & Noble, Lynch was executive vice president of marketing and general manager of HSN.com.

The company also promoted chief operating officer Mitchell Klipper to CEO of the company’s retail group, which oversees the company’s retail and college booksellers businesses.