Between the tight political race and the chaos on Wall St., Forbes.com has picked the right time to revamp its Opinions Channel. Unveiled today, the channel is structured around four main topic categories: Business and Economics, Foreign Affairs and Defense, Culture and Society, and Politics. The site will be overseen by former FT and WSJ editor Tunku Varadarajan as Opinions Channel editor, reporting to Forbes.com Managing Editor Carl Lavin. Forbes.com has also added 16 new columnists who will be writing weekly columns for the channel. Some of the new names include Reihan Salam, who will offer a look at Republican politicians after Bush in “Grand New Party” on Mondays and Nouriel Roubini, economist from the Stern Business School at NYU, who has gained notice for calling the mortgage lending crisis in advance will continue offer more pessimism in his aptly named column, “Doctor Doom.” Also Forbes magazine Publisher Rich Karlgaards’ daily tech blog “Digital Rules” will continue to run, along with his new video blog “Talk Back.”