I'd wait before forming an opinion until the report is verified by actual specialists and technicians who work with the device. The report only quotes the student with regard to the magnet/pacemaker interaction. There aren't any details on exactly how the study done, how many subjects, etc.).
Of course, as others have pointed out, this is an Apple product, so jumping to conclusions seems to be a given these days (and ignoring every other source of magnetic fields, including 3rd party accessories).
I have an implanted device myself which can be turned off and on transdermally with a magnet (though not a pacemaker, it would be a similar depth below the skin). So far, the only magnet that I can get to work with it is the stout horseshoe magnet that was given to me by the implant manufacturer. And, even then, it needs to be moving past the device through a very narrow path close to the skin. It needs to work through many millimeters of tissue, which limits how far away it can be in x, y, and z axis.
For grins, I just tried the Smart Cover, and unsurprisingly, it has no effect.
All that being said, there are many types of implants from many manufacturers, and I'm sure they have some variance in sensitivity to a controlling magnetic field. On the other hand, they can't change physics: field intensity decreases exponentially with distance. Also, there are only very limited types of detectors (they probably use Hall Effect), so the devices will all have similar specs for external control magnetic fields.