Unfortunately, it doesn't look like they'll be making an appearance nationally (at least not any time soon). I reached out to the company and a company spokesperson had this to say:
"Arby’s is committed to an ever evolving, collaborative and innovative approach to product innovation and R&D. Currently Arby’s is only testing its new Artisan Melts in Evansville, Indiana. This is simply a test of new operational processes and equipment. We have no additional test markets or product updates to share at this time."