In the past twenty years, the US Patent & Trademark Office has issued just over 268,000 design patents. During that time, almost exactly one percent (1%) of those issued design patents have been litigated to some degree. (i.e., at least a complaint was filed asserting infringement of the patent). The most commonly litigated are design patents covering ornamental features of shoes (7% of litigated patents) and lamps (5% of litigated patents). Other commonly litigated products include furniture (chairs & tables), eyeglasses, and golf equipment.
35 USC 171 outlines the scope of design patents as “any new, original, and ornamental design for an article of manufacture.” The MPEP narrows this definition to only include “visual characteristics” of a design – although a court could force the PTO to include other sensory characteristics. I suspect a product with ornamental textures – even if not visually distinct — could be protected (especially if the product was designed for blind individuals). A further (and improbable) stretch would be to define design to include associated music, scent, and taste.