You still need a craniotomy, but the dura remains mostly intact. Rodent dura is a lot thinner than in primates though, so it'll be interesting to see whether it works in larger animals. I'd also like to see some actual data showing that these electrodes last longer. People can keep Utah arrays going for a few years, even though the implantation surgery is more invasive. (craniotomy + duratomy + pneumatic insertion).

Still, it's nice to see some innovation that might eventually work in large animals and humans, instead of yet another thing that only works in transgenic mice.