Yeah, I've been keeping my eye on them for a while now.
As far as I know, they're still in pre-order and are not yet available for general purchase.
And there are some issues that I'm still very interested to see how they solve.
The biggest problem I see is flight time. If you're out doing your activity - MotoX, boarding, surfing - you could be out for hours. The last thing you want to do is pause every 20 minutes to switch out the batteries.
I'm sure they're planning on having a RTH once the battery runs low... but we've seen how well that works for the Phantom in RL. What happens if your AirDog is out shooting you catching a wave, and decides it needs to go back and land? Do you distract yourself to make sure it makes it? What if the tides coming in and where the home point is is no longer high and dry?
Oh... plus... can you imagine how many punk snowboarders will have these things following them as they're coming down the mountain? You're going to need air traffic control just to avoid getting hit.
But... those issues aside, it could be very cool. I think the AirDog is innovative in that the "AirLeash" is built to be rugged and waterproof.