I'm not aware of any postal service that uses a method other then optical imaging for address reading. Further, in some countries such as the US, it is not legal for the postal service to "look inside" mail pieces without a warrant.

While this type of 3D X-Ray technique is indeed possible it requires expensive specialized equipment and a great deal of effort, thus it being a major achievement for this university group. Or in other words, if a research group puts out a press release lauding a first, it is not likely to be a technology in use in thousands of sorting centers for millions of mail pieces daily.