The lacing itself is temporary, but can be kept with proper care. The piercings and rings can be permanent.
The piercings are what is called SURFACE PIERCINGS and a lot of shops won't do them anymore due to tearing and damage to the skin, when they are not properly cared for. Surface piercings are easy to rip from the skin if the ring gets caught on something. (Or in the case of lacing, if the laces get caught, a few of the rings may be torn out. Painful to say the least)
If the piercing is properly cared for, and not damaged, the lacings can be re-laced whenever the person wishes, changing color of the ribbon or laces to match mood, outfit, occasion, whatever.
I myself think this small clique of body piercing is very sexy and absolutely intriguing, but I don't expect to see someone in person myself. It's just not very common.