About 4,000 independent distributors crowded into the Salt Palace Convention Center to listen to the pep talks and inspirational sales messages from company officials. "This is the largest launch in the history of network marketing," said Bill Farley, CEO of the multilevel marketing company based in Draper. Amy Robinson, vice president of the Direct Selling Association, a trade group for companies that have independent sales forces who sell directly to consumers, said she didn't know of any way to compare the size of the launches of such companies.