Description:In China, they're headed home. By the hundreds of millions, all in anticipation of the lunar new year which begins on January 23. It's the largest annual human migration on the planet. Trains, buses and planes have been packed and authorities have implemented an online ticketing system to accomodate the unprecedented 3.1 billion passengers traveling over the next few weeks. So far, the new online system isn't receiveing rave review.(1:17)