Bright and early on Saturday mornings, 52 weeks a year, retail giant Wal-Mart holds its legendary Saturday Morning Meeting at the "home office" in Bentonville, Arkansas. Part pep rally, part financial update, and part merchandising workshop, there are usually around 600 people in attendance, ranging from store managers to visiting business luminaries and celebrities. The ritual is as old as Wal-Mart itself, going back to 1962, when founder Sam Walton would show up at 2 or 3 a.m. on Saturdays to see what was selling and compare the numbers with previous weeks. Then he would share his findings with...