I kind of hope they aren't caught, and it seems unlikely they will be. This hack didn't take loads of sophistication, which means the systems weren't configured in so much as a basic defensive posture, which means they probably weren't configured in a way to retain any useful logging.
In terms of the wireless signal, the police would have needed to triangulate it, or at least use a device with a directional antenna to track the user down while they were broadcasting. I've found such technical devices to be well beyond the capability of local enforcement officers who have limited training in the use of electronics. Anyone responsible for the system would have been busy fighting the fire that was the activation and subsequent inability to shut it down.
If there's a way to track the attacker, it's likely to only be through the hacked computer system.
As to my hope, they brought governmental security to the news forefront for a brief period with a nearly harmless, but highly visible hack. That deserves an award, in my book.
The fact that it pissed people off... well, they should really be directing that ire at those who configured the system without any security to begin with. If you leave your house unlocked every day, you can't be surprised if one day you find someone helped themselves to your belongings. In this case, the intruder merely left you a note "suggesting" you start locking your door. You're a damn lucky fool and should be glad the intruder was not more nefarious.