Seems cool and all, I think the price is the only advantage, really. Then again, you do have to buy a new rifle. They claim that it would drop like 3 inches at 200 yards with a 100 yd zero, while in some loadings the .17 hornet drops as much as 13. A slower bullet with the same weight drops less apparently.
With the same 20 grain loading at 3,500fps, the .17 hornet blows it out of the park, but again, the price is a factor too, I guess. What I would like to see is possibly a .22 version, which I don't think exists, but I'm sure they'll come out with it. I want there to be a new "king" of rimfire above the .22wmr (which I love) and if they would beef up the cartridge, I would be a happy camper.
I'd be delighted to see a 40 grain at mid 2000's fps. That would be a hell of a cartridge, I think. Can a .17WSM rifle chamber .17HMR? It appears to be the same in case dimension, and the Winchester Super Magnum designation implies it. All the more reason to make a .22 version!