When in the last 10 years has Apple ever updated a computers ports without a full redesign?
I can think of one time. My Early 2011 MacBook Pro was just a refresh and it kept the 2008 design, however Apple added a Thunderbolt port. Of course, the Thunderbolt interface used the Mini Display port, but I think it might count.
Late 2008 to Mid 2009 13" MBP added SD Card reader and Firewire with no other cosmetic changes (this transformed the Unibody 13" MB into the 13" MBP).