Eric Schlosser is quick to point out that 2006 represents an important, but mostly overlooked, centennial. In his first opportunity to speak following the D.C. premiere of the movie based on his book, Fast Food Nation, Schlosser reminds the audience that it was in 1906 that Upton Sinclair published The Jungle, the classic muckraker that exposed the horrific practices of the meatpacking industry and helped prompt a major overhaul in the way they conducted their…