Now that Saab has finally gotten the new 9-5 into production, Trollhattan is turning its full attention to the next big challenge: a new 9-3 for model year 2013. At least it should look good -- Saab has just employed one of the world's hottest designers.Jason Castriota worked at Pininfarina, where he helped pen the Maserati GranTurismo and influence the Ferrari 599. He also headed the special projects division that produced the knee-trembling Maserati Birdcage 75 and Ferrari P4/5. Castriota then went to Bertone and produced perhaps his greatest piece, the Corvette ZR1-based Mantide, which projects the spirit of Bertone's 1970s mania into a modern-day form.