Yes, new designs are on the way! People have been inquiring, and I can assure you we are hard at work*.
*If by “work” you mean shooting an MP5 machine gun with a hangover at a Capcom event in Vegas, then yes, we are working.
People have also been asking, “What are the Mario pins [that are included with the shirts] all about?”, and “Can I buy more?” To answer the first question: they made their debut here, and then went on to do TV, and now there are even rumors of a book deal. To answer the second question: sadly no, they are not for sale. We insist on charging zero for them. If you really want the complete set of 64 Marios, two pins are always included with each shirt design.