Transpera, the largest mobile video ad network in North America, has lined up many of the industry's leading publishers including msnbc.com, CBS.com, Showtime, Disney and MTV. In this interview, Transpera CEO Frank Barbieri explains video advertising is working well for publishers. He says that inventory is nearly sold out for Q4 and publishers are enjoying substanially higher advertising rates to comparable online ads. I spoke with him before the Beet.TV Online Video Roundtable in New York.Andy Plesser, Executive Producer Less