A surprising move from Barnes & Noble CEO Steve Riggio is stepping down from that role for William Lynch, who joined in early 2009 as president of BN.com (NYSE: BKS). Riggio stays as vice chairman and insists he will still be actively involved. At the same time, B&N promoted COO Mitchell Klipper to CEO of the company’s retail group, which houses the retail stores and the Barnes & Noble College Booksellers.

Lynch’s promotion over Kipper, a 23-year vet, highlights the shift in B&N’s business from retail bookstores to a multplatform company increasingly focused on digital through its own Nook e-reader, its e-bookstore, which also serves other devices, and its eReader platform. Lynch is credited with propelling B&N into the digital age, or as Riggio said in the announcement, “quickly establishing Barnes & Noble as a major player in e-commerce and digital content.”