For U.S./Canada 2013 Audi = 2012 Audi.
The OP had a link to the German Audi brochure for "Der neue A3"--the new 3-door based on the MQB platform--which we're never going to get over here. I then pointed out that the 2013 A3s that Audi will be bringing will have no new features and will be identical to the 2012 A3s.
The 4-door sedan A3s will most likely appear as 2014 models sometime late next year. I'd be surprised if they bring an MQB-based 5-door here.
2007 A3 S-Line 2.0T manual GIAC