"Shooting down a single artillery shell is pretty cool, but artillery shells don't come in ones,"
As they get smaller, deploying several of these and linking them via wireless to a central supercomputer would be quite potent. They could target and hit multiple incoming rounds without duplicate targeting.
In addition, this technology could be adapted for other uses. Target enemy units from far greater distances than conventional weaponry allows. Heck, use it as a "sniper" device. Pick them off one unit at a time until they all hide in a bunker, then Fuel-Air Bomb the bunkers.
And I'm sure it could hit a slow moving target much easier than a rocket.